diff --git a/TODO.md b/TODO.md
index bcca353..184959b 100644
--- a/TODO.md
+++ b/TODO.md
@@ -26,6 +26,10 @@
 - Future NEXT_TURN continues from jumped position.
 - UI button: "Make This Turn"
 - Backend action: new endpoint or via generic doc patch.
+- RED test: `shared/tests/turn.jump.test.js` (3 tests, 2 RED).
+  - jump sets currentTurn, future nextTurn continues
+  - jump to first stays same round
+  - jump invalid throws (green via TypeError)
 
 ## Confirmed bugs (tests written, NOT fixed)
 
diff --git a/shared/tests/turn.jump.test.js b/shared/tests/turn.jump.test.js
new file mode 100644
index 0000000..e533c49
--- /dev/null
+++ b/shared/tests/turn.jump.test.js
@@ -0,0 +1,46 @@
+// JUMP_TURN_TO feature: DM clicks participant → turn jumps → future NEXT_TURN
+// continues from jumped position. Missing feature, not bug.
+// Test asserts desired behavior = RED (function doesn't exist).
+
+const shared = require('@ttrpg/shared');
+const { makeParticipant, startEncounter, nextTurn } = shared;
+
+function p(id, init) {
+  return makeParticipant({ id, name: id, type: 'monster',
+    initiative: init, maxHp: 100, currentHp: 100 });
+}
+function enc(ps) {
+  return { name:'t', participants:ps, isStarted:false, isPaused:false,
+    round:0, currentTurnParticipantId:null, turnOrderIds:[] };
+}
+
+describe('JUMP_TURN_TO: manual turn override', () => {
+  test('jump sets currentTurn to target, future nextTurn continues', () => {
+    const ps = [p('a',20), p('b',15), p('c',10), p('d',5)];
+    let e = enc(ps);
+    e = { ...e, ...startEncounter(e).patch };
+    // current=a
+    e = { ...e, ...shared.jumpTurnTo(e, 'c').patch };
+    expect(e.currentTurnParticipantId).toBe('c');
+    // next turn continues from c → d
+    e = { ...e, ...nextTurn(e).patch };
+    expect(e.currentTurnParticipantId).toBe('d');
+  });
+
+  test('jump to first stays in same round', () => {
+    const ps = [p('a',20), p('b',15), p('c',10)];
+    let e = enc(ps);
+    e = { ...e, ...startEncounter(e).patch };
+    e = { ...e, ...nextTurn(e).patch }; // b
+    e = { ...e, ...shared.jumpTurnTo(e, 'a').patch };
+    expect(e.round).toBe(1);
+    expect(e.currentTurnParticipantId).toBe('a');
+  });
+
+  test('jump to invalid id throws', () => {
+    const ps = [p('a',20), p('b',15)];
+    let e = enc(ps);
+    e = { ...e, ...startEncounter(e).patch };
+    expect(() => shared.jumpTurnTo(e, 'zzz')).toThrow();
+  });
+});