diff --git a/tests/unit/runtime-host.test.ts b/tests/unit/runtime-host.test.ts
index d770671e..c97c0ddc 100644
--- a/tests/unit/runtime-host.test.ts
+++ b/tests/unit/runtime-host.test.ts
@@ -2,17 +2,23 @@ import { waitFor } from "@testing-library/react";
 import { afterEach, describe, expect, it, vi } from "vitest";
 
 import {
+  createActorControlTargetRef,
   createLightControlTargetRef,
+  createSetActorPresenceControlEffect,
   type ControlEffect,
   createSetLightEnabledControlEffect,
   createSetLightIntensityControlEffect
 } from "../../src/controls/control-surface";
 import { createEmptySceneDocument } from "../../src/document/scene-document";
-import { createPointLightEntity } from "../../src/entities/entity-instances";
+import {
+  createNpcEntity,
+  createPointLightEntity
+} from "../../src/entities/entity-instances";
 import {
   createControlInteractionLink,
   type InteractionLink
 } from "../../src/interactions/interaction-links";
+import { createProjectScheduleRoutine } from "../../src/scheduler/project-scheduler";
 import { RapierCollisionWorld } from "../../src/runtime-three/rapier-collision-world";
 import {
   RuntimeHost,
@@ -195,4 +201,86 @@ describe("RuntimeHost", () => {
 
     host.dispose();
   });
+
+  it("re-resolves NPC activity from the project scheduler when the runtime clock advances", () => {
+    vi.spyOn(console, "warn").mockImplementation(() => undefined);
+    vi.spyOn(RapierCollisionWorld, "create").mockResolvedValue({
+      dispose: vi.fn(),
+      resolveThirdPersonCameraCollision: vi.fn(
+        (_pivot, desiredCameraPosition) => desiredCameraPosition
+      )
+    } as unknown as RapierCollisionWorld);
+
+    const npc = createNpcEntity({
+      id: "entity-npc-night-guard",
+      actorId: "actor-night-guard"
+    });
+    const document = createEmptySceneDocument();
+    document.entities[npc.id] = npc;
+    document.scheduler.routines["routine-night-guard"] =
+      createProjectScheduleRoutine({
+        id: "routine-night-guard",
+        title: "Night Shift",
+        target: createActorControlTargetRef(npc.actorId),
+        startHour: 20,
+        endHour: 4,
+        effect: createSetActorPresenceControlEffect({
+          target: createActorControlTargetRef(npc.actorId),
+          active: true
+        })
+      });
+
+    const runtimeScene = buildRuntimeSceneFromDocument(document);
+    const host = new RuntimeHost({
+      enableRendering: false
+    });
+    host.loadScene(runtimeScene);
+
+    const hostInternals = host as unknown as {
+      currentClockState: {
+        timeOfDayHours: number;
+        dayCount: number;
+        dayLengthMinutes: number;
+      } | null;
+      sceneReady: boolean;
+      runtimeScene: typeof runtimeScene | null;
+      syncRuntimeNpcScheduleToCurrentClock(): void;
+    };
+
+    expect(runtimeScene.entities.npcs).toEqual([]);
+
+    hostInternals.sceneReady = true;
+    hostInternals.currentClockState = {
+      timeOfDayHours: 21,
+      dayCount: 0,
+      dayLengthMinutes: 24
+    };
+    hostInternals.syncRuntimeNpcScheduleToCurrentClock();
+
+    expect(hostInternals.runtimeScene?.entities.npcs).toEqual([
+      expect.objectContaining({
+        entityId: npc.id,
+        actorId: npc.actorId,
+        activeRoutineTitle: "Night Shift"
+      })
+    ]);
+
+    hostInternals.currentClockState = {
+      timeOfDayHours: 6,
+      dayCount: 1,
+      dayLengthMinutes: 24
+    };
+    hostInternals.syncRuntimeNpcScheduleToCurrentClock();
+
+    expect(hostInternals.runtimeScene?.entities.npcs).toEqual([]);
+    expect(hostInternals.runtimeScene?.npcDefinitions[0]).toEqual(
+      expect.objectContaining({
+        entityId: npc.id,
+        active: false,
+        activeRoutineTitle: null
+      })
+    );
+
+    host.dispose();
+  });
 });