diff --git a/components/reasoning-workspace.jsx b/components/reasoning-workspace.jsx
index 5e1d4c7..db810c3 100644
--- a/components/reasoning-workspace.jsx
+++ b/components/reasoning-workspace.jsx
@@ -47,6 +47,13 @@ const UPDATE_MESSAGES = [
   { min: 45, text: "Choosing the next question" },
 ];
 
+const REVISION_MESSAGES = [
+  { min: 0, text: "Reading what changed" },
+  { min: 10, text: "Rebuilding the investigation" },
+  { min: 25, text: "Checking what this affects" },
+  { min: 45, text: "Choosing the next justified question" },
+];
+
 function useLoadingStatus(messages, isLoading) {
   const [elapsed, setElapsed] = useState(0);
   const startRef = useRef(null);
@@ -76,6 +83,59 @@ function useLoadingStatus(messages, isLoading) {
   return { elapsed, currentMessage };
 }
 
+// ── Revision warning banner ─────────────────────────────────
+function RevisionWarningCard() {
+  return (
+    <div className="rounded-lg border border-amber-200 bg-amber-50 px-5 py-3 text-sm text-amber-900">
+      Changing this answer may alter the questions and conclusions that followed it.
+    </div>
+  );
+}
+
+// ── Revision inline editor ────────────────────────────────────
+function RevisionEditor({ turn, onSave, onCancel }) {
+  const [draft, setDraft] = useState(turn.answer);
+
+  return (
+    <div className="rounded-lg border border-amber-200 bg-amber-50 px-5 py-4 space-y-3">
+      <RevisionWarningCard />
+      <p className="text-sm font-medium text-amber-900">{turn.question}</p>
+      <textarea
+        value={draft}
+        onChange={(e) => setDraft(e.target.value)}
+        rows={3}
+        className="w-full rounded-lg border border-amber-300 bg-white px-4 py-2 text-sm focus:border-amber-400 focus:outline-none"
+      />
+      <div className="flex gap-3">
+        <button
+          type="button"
+          onClick={() => onSave(draft)}
+          disabled={!draft.trim()}
+          className="rounded-lg bg-amber-600 px-4 py-2 text-sm font-medium text-white hover:bg-amber-700 disabled:opacity-40"
+        >
+          Save revised answer
+        </button>
+        <button
+          type="button"
+          onClick={onCancel}
+          className="text-sm text-amber-700 underline hover:text-amber-900"
+        >
+          Cancel
+        </button>
+      </div>
+    </div>
+  );
+}
+
+// ── Stale turn summary (shown under "Earlier answers that may need reviewing") ───
+function StaleTurnSummary({ turn, index }) {
+  return (
+    <div className="rounded-lg border border-red-100 bg-red-50/40 px-4 py-2 text-sm text-red-800">
+      <span className="font-medium">Earlier answer #{index + 1}:</span> {turn.question} — "{turn.answer}" may no longer apply.
+    </div>
+  );
+}
+
 // ── Spinner component ───────────────────────────────────────
 function ActivitySpinner() {
   return (
@@ -198,40 +258,62 @@ function CurrentFocusCard({ graph }) {
 }
 
 // ── Investigation history card ────────────────────────────────
-function InvestigationHistoryCard({ turn }) {
+function InvestigationHistoryCard({ turn, onReview }) {
+  const hasReview = !onReview && turn.status === "current";
+
   return (
-    <details className="rounded-lg border border-gray-100 bg-gray-50/60 px-4 py-3">
-      <summary className="cursor-pointer text-xs font-semibold uppercase tracking-wide text-gray-400 hover:text-gray-600">
-        {new Date(turn.timestamp).toLocaleString(undefined, {
-          month: "short",
-          day: "numeric",
-          hour: "2-digit",
-          minute: "2-digit",
-        })}
-      </summary>
-      <div className="mt-2 space-y-2 text-sm">
-        <p><strong>{turn.question}</strong></p>
-        <p className="text-gray-700">{turn.answer}</p>
-        {turn.engineResponse && (
-          <p className="italic text-gray-500">{turn.engineResponse}</p>
+    <div className="rounded-lg border border-gray-100 bg-gray-50/60 px-4 py-3">
+      <div className="flex items-start justify-between gap-3">
+        <div>
+          <p className="text-xs text-gray-400">
+            {new Date(turn.timestamp).toLocaleString(undefined, {
+              month: "short",
+              day: "numeric",
+              hour: "2-digit",
+              minute: "2-digit",
+            })}
+          </p>
+          <details className="mt-1">
+            <summary className="cursor-pointer text-xs font-semibold uppercase tracking-wide text-gray-400 hover:text-gray-600">
+              {turn.question}
+            </summary>
+            <div className="mt-2 space-y-2 text-sm">
+              <p><strong>You told us:</strong> {turn.answer}</p>
+              {turn.engineResponse && (
+                <p className="italic text-gray-500">{turn.engineResponse}</p>
+              )}
+            </div>
+          </details>
+        </div>
+        {hasReview && (
+          <button
+            type="button"
+            onClick={onReview}
+            className="shrink-0 rounded border border-gray-300 bg-white px-3 py-1 text-xs font-medium text-gray-600 hover:bg-gray-100 hover:text-gray-900"
+          >
+            Review answer
+          </button>
         )}
       </div>
-    </details>
+    </div>
   );
 }
 
 // ── Investigation history section ─────────────────────────────
-function InvestigationHistory({ turns }) {
+function InvestigationHistory({ turns, onReviewTurn }) {
   if (!turns || turns.length === 0) return null;
 
+  const activeTurns = turns.filter((t) => t.status !== "superseded");
+  if (activeTurns.length === 0) return null;
+
   return (
     <div className="space-y-3">
       <h2 className="text-xs font-bold uppercase tracking-wider text-gray-400">
         Investigation history
       </h2>
       <div className="space-y-2">
-        {turns.map((turn, idx) => (
-          <InvestigationHistoryCard key={idx} turn={turn} />
+        {activeTurns.map((turn, idx) => (
+          <InvestigationHistoryCard key={turn.id ?? idx} turn={turn} onReview={turn.status === "current" ? () => onReviewTurn?.(idx) : undefined} />
         ))}
       </div>
     </div>
@@ -382,9 +464,18 @@ export default function ReasoningWorkspace({
   setAnswer,
   onAnswerSubmit,
   lastSubmittedAnswer,
+  isRevisionLoading: propIsRevisionLoading,
 }) {
   const [investigationHistory, setInvestigationHistory] = useState([]);
 
+  // Inline revision editor state (local — no parent re-render until submit)
+  const [editingTurnIndex, setEditingTurnIndex] = useState(-1);
+  const [revisionDraft, setRevisionDraft] = useState("");
+  const [showRevisionEditor, setShowRevisionEditor] = useState(false);
+
+  // Track which turn was revised so we can mark stale turns after update succeeds
+  const revisedTurnIndexRef = useRef(-1);
+
   // Capture the previous question before each new question is set
   const prevQuestionRef = useRef(null);
   const hasCapturedInitialQuestion = useRef(false);
@@ -396,22 +487,39 @@ export default function ReasoningWorkspace({
     }
   }, [result?.selectedQuestion]);
 
-  // Append completed turn to history after a successful update
+  // Append completed turn to history after a successful update (normal or revision)
   useEffect(() => {
-    if (updateStatus === "success" && lastSubmittedAnswer) {
-      const q = prevQuestionRef.current;
-      setInvestigationHistory((prev) => [
-        ...prev,
-        {
-          question: typeof q === "string" ? q : q?.question ?? "",
-          answer: lastSubmittedAnswer,
-          engineResponse: result?.summary || null,
-          timestamp: Date.now(),
-        },
-      ]);
-    }
+    if (updateStatus !== "success" || !lastSubmittedAnswer) return;
+
+    const q = prevQuestionRef.current;
+    setInvestigationHistory((prev) => {
+      const newTurn = {
+        id: Date.now(),
+        question: typeof q === "string" ? q : q?.question ?? "",
+        answer: lastSubmittedAnswer,
+        engineResponse: result?.summary || null,
+        graphBeforeAnswer: result?.situationGraph ? JSON.parse(JSON.stringify(result.situationGraph)) : null,
+        selectedQuestionBeforeAnswer: q,
+        timestamp: Date.now(),
+        status: "current",
+      };
+
+      // If this was a revision, mark the target turn as superseded and all later turns as stale
+      const revIdx = revisedTurnIndexRef.current;
+      if (revIdx >= 0) {
+        return prev.map((t, i) => {
+          if (i === revIdx) return { ...t, status: "superseded" };
+          if (i > revIdx) return { ...t, status: t.status === "superseded" ? "superseded" : "stale" };
+          return t;
+        }).concat(newTurn);
+      }
+
+      return [...prev, newTurn];
+    });
+    revisedTurnIndexRef.current = -1;
   }, [updateStatus, lastSubmittedAnswer]);
 
+  const isRevisionLoading = propIsRevisionLoading || false;
   const { elapsed: startElapsed, currentMessage: startMsg } = useLoadingStatus(
     INITIAL_MESSAGES,
     status === "loading"
@@ -428,6 +536,7 @@ export default function ReasoningWorkspace({
   const canAnswer =
     status === "success" &&
     !isUpdating &&
+    !isRevisionLoading &&
     Boolean(result?.situationGraph) &&
     hasSelectedQuestion;
 
@@ -439,6 +548,36 @@ export default function ReasoningWorkspace({
 
   const genuineCompletion = hasGenuineCompletion(graph);
 
+  // Filter turns into active and stale groups after revision
+  const activeTurns = investigationHistory.filter((t) => t.status !== "superseded");
+  const staleTurns = investigationHistory.filter((t) => t.status === "superseded");
+
+  // Open inline revision editor for a specific turn
+  function openRevisionEditor(idx) {
+    const turn = investigationHistory[idx];
+    if (!turn) return;
+    setEditingTurnIndex(idx);
+    setRevisionDraft(turn.answer);
+    setShowRevisionEditor(true);
+  }
+
+  function closeRevisionEditor() {
+    setEditingTurnIndex(-1);
+    setShowRevisionEditor(false);
+    setRevisionDraft("");
+  }
+
+  // Save revised answer — use graph checkpoint from the target turn,
+  // or fall back to the current situationGraph as a replay starting point.
+  function saveRevision(draft) {
+    if (!draft?.trim()) return;
+    closeRevisionEditor();
+    const checkpoint = investigationHistory[editingTurnIndex]?.graphBeforeAnswer ?? graph;
+    revisedTurnIndexRef.current = editingTurnIndex;
+    setAnswer(draft.trim());
+    onAnswerSubmit({ preventDefault: () => {} }, { graphCheckpoint: checkpoint, turnIndex: editingTurnIndex });
+  }
+
   return (
     <div className="space-y-5">
       {/* ── Loading overlays ─────────────────────────────── */}
@@ -470,11 +609,32 @@ export default function ReasoningWorkspace({
           {/* Post-update acknowledgement */}
           {updateStatus === "success" && canAnswer && <UpdateAcknowledgement updateResult={result} />}
 
-          {/* Completion state */}
-          {status === "success" && !canAnswer && graph && genuineCompletion && (
+          {/* Revision editor inline */}
+          {showRevisionEditor && investigationHistory[editingTurnIndex] && (
+            <RevisionEditor
+              turn={investigationHistory[editingTurnIndex]}
+              onSave={(draft) => saveRevision(draft)}
+              onCancel={closeRevisionEditor}
+            />
+          )}
+
+          {/* Stale turns summary — shown after revision */}
+          {staleTurns.length > 0 && (
+            <div className="space-y-2">
+              <h3 className="text-xs font-bold uppercase tracking-wider text-gray-400">
+                Earlier answers that may need reviewing
+              </h3>
+              {staleTurns.map((turn, idx) => (
+                <StaleTurnSummary key={turn.id} turn={turn} index={idx} />
+              ))}
+            </div>
+          )}
+
+          {/* Completion state — suppressed during any loading or revision */}
+          {status === "success" && !canAnswer && graph && genuineCompletion && !isRevisionLoading && (
             <InvestigationCompleteMessage noQuestionReason={noQuestionReason} />
           )}
-          {status === "success" && !canAnswer && graph && !genuineCompletion && updateStatus !== "success" && (
+          {status === "success" && !canAnswer && graph && !genuineCompletion && updateStatus !== "success" && !isRevisionLoading && (
             <div className="rounded-lg border border-gray-200 bg-gray-50 px-5 py-4 text-center">
               <p className="text-sm text-gray-600">There is no further question the engine can justify at the moment.</p>
               <p className="mt-1 text-xs text-gray-500">More evidence may be needed before a next step is clear.</p>
@@ -522,7 +682,7 @@ export default function ReasoningWorkspace({
           )}
 
           {/* ── Investigation history (below the answer form) ─ */}
-          <InvestigationHistory turns={investigationHistory} />
+          <InvestigationHistory turns={activeTurns} onReviewTurn={openRevisionEditor} />
 
           {/* ── Developer details (collapsed by default) ─── */}
           {(status === "success" || status === "error") && graph && (
@@ -556,4 +716,4 @@ export default function ReasoningWorkspace({
   );
 }
 
-export { useLoadingStatus, INITIAL_MESSAGES, UPDATE_MESSAGES, LoadingOverlay, resolveCurrentSummary, isTechnicalSummary };
+export { useLoadingStatus, INITIAL_MESSAGES, UPDATE_MESSAGES, REVISION_MESSAGES, LoadingOverlay, resolveCurrentSummary, isTechnicalSummary };
diff --git a/components/scenario-form.jsx b/components/scenario-form.jsx
index 904e3c4..8e0c47a 100644
--- a/components/scenario-form.jsx
+++ b/components/scenario-form.jsx
@@ -100,6 +100,16 @@ export function ScenarioResultPanels({ status, result }) {
   );
 }
 
+// ── Spinner for revision loading overlay ─────────────────────
+function RevisionSpinner() {
+  return (
+    <span
+      className="inline-block h-4 w-4 border-[2px] border-gray-300 border-t-amber-600 rounded-full"
+      style={{ animation: "spin 1s linear infinite" }}
+    />
+  );
+}
+
 // ── Message pools ───────────────────────────────────────────
 const INITIAL_MESSAGES = [
   { min: 0, text: "Reading your situation" },
@@ -115,6 +125,13 @@ const UPDATE_MESSAGES = [
   { min: 45, text: "Choosing the next question" },
 ];
 
+const REVISION_MESSAGES = [
+  { min: 0, text: "Reading what changed" },
+  { min: 10, text: "Rebuilding the investigation" },
+  { min: 25, text: "Checking what this affects" },
+  { min: 45, text: "Choosing the next justified question" },
+];
+
 function useLoadingStatus(messages, isLoading) {
   const [elapsed, setElapsed] = useState(0);
   const startRef = useRef(null);
@@ -189,8 +206,12 @@ export default function ScenarioForm() {
   const [updateError, setUpdateError] = useState(null);
   const [updateResult, setUpdateResult] = useState(null);
   const [lastSubmittedAnswer, setLastSubmittedAnswer] = useState("");
+  const [isRevisionLoading, setIsRevisionLoading] = useState(false);
+  const [revisionTurnIndex, setRevisionTurnIndex] = useState(-1);
   const textareaRef = useRef(null);
 
+  // Loading state tracking for normal update vs revision
+  const isAnyUpdateLoading = updateStatus === "loading" || isRevisionLoading;
   const { elapsed: startElapsed, currentMessage: startMsg } = useLoadingStatus(
     INITIAL_MESSAGES,
     status === "loading"
@@ -198,7 +219,12 @@ export default function ScenarioForm() {
 
   const { elapsed: updateElapsed, currentMessage: updateMsg } = useLoadingStatus(
     UPDATE_MESSAGES,
-    updateStatus === "loading"
+    updateStatus === "loading" && !isRevisionLoading
+  );
+
+  const { elapsed: revisionElapsed, currentMessage: revisionMsg } = useLoadingStatus(
+    REVISION_MESSAGES,
+    isRevisionLoading
   );
 
   const handleSubmit = async (e) => {
@@ -231,7 +257,7 @@ export default function ScenarioForm() {
     }
   };
 
-  const handleUpdate = async (e) => {
+  const handleUpdate = async (e, options = {}) => {
     e.preventDefault();
 
     // Guard empty answer before showing loading state
@@ -241,19 +267,25 @@ export default function ScenarioForm() {
       return;
     }
 
+    const isRevision = !!options.graphCheckpoint;
+    const turnIndex = options.turnIndex ?? revisionTurnIndex;
+
     setUpdateStatus("loading");
+    setIsRevisionLoading(isRevision);
+    if (isRevision) setRevisionTurnIndex(turnIndex);
     setUpdateError(null);
     setLastSubmittedAnswer(answer.trim());
 
     const submission = await submitAnswerForUpdateCase(fetch, {
-      situationGraph: result?.situationGraph,
-      previousQuestion: result?.selectedQuestion,
+      situationGraph: options.graphCheckpoint ?? result?.situationGraph,
+      previousQuestion: isRevision ? undefined : result?.selectedQuestion,
       answer,
     });
 
     if (submission.skipped) {
       setUpdateStatus("error");
       setUpdateError(submission.data);
+      setIsRevisionLoading(false);
       return;
     }
 
@@ -261,10 +293,11 @@ export default function ScenarioForm() {
       const outcome = submission.data;
 
       if (submission.ok && outcome.success) {
+        if (isRevision) setIsRevisionLoading(false);
         setUpdateStatus("success");
         setUpdateResult({
           ...outcome,
-          previousSituationGraph: result?.situationGraph ?? null,
+          previousSituationGraph: options.graphCheckpoint ?? result?.situationGraph ?? null,
         });
         setResult((current) => ({
           ...current,
@@ -280,10 +313,12 @@ export default function ScenarioForm() {
         setAnswer("");
       } else {
         setUpdateStatus("error");
+        setIsRevisionLoading(false);
         setUpdateError(outcome);
       }
     } catch (err) {
       setUpdateStatus("error");
+      setIsRevisionLoading(false);
       setUpdateError({ error: err.message || "Network request failed" });
     }
   };
@@ -316,7 +351,7 @@ export default function ScenarioForm() {
       </form>
 
       {/* ── Initial analysis loading card ─────────────── */}
-      {status === "loading" && (
+      {status === "loading" && !isRevisionLoading && (
         <LoadingOverlay
           isLoading={true}
           elapsed={startElapsed}
@@ -325,6 +360,17 @@ export default function ScenarioForm() {
         />
       )}
 
+      {/* ── Revision loading card ─────────────────────── */}
+      {isRevisionLoading && (
+        <div className="rounded-lg border border-amber-200 bg-amber-50 px-5 py-6" role="status" aria-busy="true">
+          <div className="flex items-center gap-3">
+            <RevisionSpinner />
+            <span className="text-base font-medium text-amber-900">Considering your revised answer</span>
+          </div>
+          <p className="mt-2 text-sm text-amber-700">{revisionMsg}</p>
+        </div>
+      )}
+
       {/* ── Main result workspace ─────────────────────── */}
       {(status === "success" || status === "error" || updateStatus === "success") && (
         <ReasoningWorkspace
@@ -342,6 +388,7 @@ export default function ScenarioForm() {
           setAnswer={setAnswer}
           onAnswerSubmit={handleUpdate}
           lastSubmittedAnswer={lastSubmittedAnswer}
+          isRevisionLoading={isRevisionLoading}
         />
       )}