diff --git a/CLAUDE.md b/CLAUDE.md
index 01f9d01..777d824 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -112,8 +112,10 @@ Operational gotchas (all observed live on a Bridge Pro):
 
 When the TV is on, a configured set of viewing lights holds a steady "TV mode"
 bias look **while the rest of the home keeps driving the circadian curve**;
-when the TV turns off each light returns to its configured idle behaviour
-(`circadian` rejoins the curve, `off` goes dark). This is built **into the
+when the TV turns off each light returns to its configured idle behaviour.
+Being on TV duty is the *only* thing that sets a bias light apart from the
+rest of the home — TV off means rejoin whatever theme everyone else is on,
+not switch to a separate schedule of its own. This is built **into the
 circadian daemon** (`circadian_daemon.py` + pure `bias_control.py`), NOT as a
 bridge scene — a single-grouped_light, suspend-on-override daemon can't hold a
 sub-zone while the rest keeps moving. See
@@ -123,6 +125,13 @@ sub-zone while the rest keeps moving. See
 How it works (config: `circadian_daemon.bias`):
 - **Per-light** drive of the bias set; the daemon owns the look
   (`bias.lights[*].look`) and each light's `idle` (`circadian` or `off`).
+  `idle: circadian` follows the curve while in-window, and — since
+  2026-08-08 — holds `night_look` out of window instead of going dark, if
+  `night_look` is configured (falls back to off if it isn't). Going fully
+  dark on its own overnight, independent of TV state, read as broken, not
+  intentional, when it first shipped (live report 2026-08-08): the whole
+  point is TV-on being the one exception, not a standing "viewing set"
+  identity with its own day/night rules.
 - **No bias light may sit in the daemon's driven zone** or the 60 s
   grouped_light tick stomps its held look. Keep the driven zone and the bias
   set disjoint.
diff --git a/hueman/bias_control.py b/hueman/bias_control.py
index 91a822e..58f660d 100644
--- a/hueman/bias_control.py
+++ b/hueman/bias_control.py
@@ -62,16 +62,27 @@ def bias_actions(
     tv_on: bool,
     in_window: bool,
     curve: DriveTo | None,
+    night_look: LightState | None = None,
     transition_ms: int,
     fade_off_ms: int,
     edge: bool = False,
 ) -> list[BiasHold | BiasDrive | BiasOff]:
     """Return the per-light action for each bias light this tick.
 
-    * ``tv_on`` -> every light holds its ``look``.
-    * otherwise ``idle == "circadian"`` and ``in_window`` and a ``curve`` sample is
-      available -> follow the curve (same brightness/mirek as the main set).
-    * otherwise (``idle == "off"``, out of window, or no curve) -> fade off.
+    * ``tv_on`` -> every light holds its ``look`` — the only case any light is
+      handled *differently* from the rest of the home; this is a TV-on-only
+      override, not a standing "viewing set" identity.
+    * otherwise ``idle == "circadian"``: join whatever the rest of the home is
+      doing. In window with a ``curve`` sample -> follow the curve (same
+      brightness/mirek as the main set). Out of window (or in window with no
+      curve sample) and ``night_look`` is configured -> hold that same look,
+      same as the main zone's own parked state — a circadian-idle light must
+      never go dark on its own just because the window closed; it should read
+      as part of one home, not a separate "viewing" island (observed live
+      2026-08-08: TV-viewing lights going fully off overnight while the rest
+      of the home sat at a dim night_look read as broken, not "TV is off").
+    * otherwise (``idle == "off"``, or ``idle == "circadian"`` with no
+      ``night_look`` and no curve) -> fade off.
 
     ``edge`` marks a committed TV-state flip: every action then fades over the
     short ``spec.transition_ms`` instead of the steady-state ``transition_ms``/
@@ -85,6 +96,8 @@ def bias_actions(
             actions.append(BiasHold(light.name, light.look, fade))
         elif light.idle == "circadian" and in_window and curve is not None:
             actions.append(BiasDrive(light.name, curve.brightness, curve.mirek, fade))
+        elif light.idle == "circadian" and night_look is not None:
+            actions.append(BiasHold(light.name, night_look, fade))
         else:
             actions.append(BiasOff(light.name, off_fade))
     return actions
diff --git a/hueman/circadian_daemon.py b/hueman/circadian_daemon.py
index f7010b7..e9b600e 100644
--- a/hueman/circadian_daemon.py
+++ b/hueman/circadian_daemon.py
@@ -670,6 +670,7 @@ def _apply_bias(self, now: float) -> None:
         latch = True   # clears only on a *transient* failure worth retrying
         for action in bias_actions(
             bias, tv_on=tv_on, in_window=in_window, curve=curve,
+            night_look=self._spec.night_look,
             transition_ms=self._spec.transition_ms, fade_off_ms=self._spec.fade_off_ms,
             edge=edge,
         ):
diff --git a/tests/test_bias_control.py b/tests/test_bias_control.py
index ba763bd..1d63a38 100644
--- a/tests/test_bias_control.py
+++ b/tests/test_bias_control.py
@@ -58,20 +58,41 @@ def test_tv_off_in_window_circadian_drives_off_idles() -> None:
     assert actions["Couch"].transition_ms == 75_000
 
 
-def test_tv_off_out_of_window_all_off() -> None:
-    """TV off, out of window: even circadian-idle lights go off."""
+def test_tv_off_out_of_window_no_night_look_goes_off() -> None:
+    """TV off, out of window, no night_look configured: circadian-idle falls back to off."""
     spec = _spec(("Couch", "circadian"))
     actions = bias_actions(spec, tv_on=False, in_window=False, curve=None,
                            transition_ms=75_000, fade_off_ms=90_000)
     assert isinstance(actions[0], BiasOff)
 
 
-def test_circadian_idle_without_curve_goes_off() -> None:
-    """In window but no curve sample available -> circadian idle falls back to off."""
+def test_tv_off_out_of_window_joins_the_night_look() -> None:
+    """TV off, out of window, night_look configured: circadian-idle lights join
+    it instead of going dark -- the only thing that handles a light DIFFERENTLY
+    from the rest of the home is the TV being on; TV off should read as one
+    home, not a separate 'viewing set' that goes dark on its own schedule
+    (observed live 2026-08-08: this looked broken, not intentional)."""
+    look = LightState(on=True, brightness=1.0, color=Color(mode="xy", hex="ff0000"))
+    spec = _spec(("Couch", "circadian"), ("Play bars", "off"))
+    actions = {a.light: a for a in bias_actions(
+        spec, tv_on=False, in_window=False, curve=None, night_look=look,
+        transition_ms=75_000, fade_off_ms=90_000)}
+    assert isinstance(actions["Couch"], BiasHold)
+    assert actions["Couch"].look == look
+    assert isinstance(actions["Play bars"], BiasOff)   # idle=off is unaffected either way
+
+
+def test_circadian_idle_without_curve_falls_back_to_night_look_when_in_window() -> None:
+    """In window but no curve sample available: falls back to night_look if set
+    (same 'never go dark on your own' rule), otherwise off."""
+    look = LightState(on=True, brightness=1.0, color=Color(mode="xy", hex="ff0000"))
     spec = _spec(("Couch", "circadian"))
-    actions = bias_actions(spec, tv_on=False, in_window=True, curve=None,
-                           transition_ms=75_000, fade_off_ms=90_000)
-    assert isinstance(actions[0], BiasOff)
+    with_look = bias_actions(spec, tv_on=False, in_window=True, curve=None, night_look=look,
+                             transition_ms=75_000, fade_off_ms=90_000)
+    assert isinstance(with_look[0], BiasHold) and with_look[0].look == look
+    without_look = bias_actions(spec, tv_on=False, in_window=True, curve=None,
+                                transition_ms=75_000, fade_off_ms=90_000)
+    assert isinstance(without_look[0], BiasOff)
 
 
 def _spec_edge(*lights: tuple[str, str], edge_ms: int = 2_000) -> BiasSpec:
diff --git a/tests/test_circadian_daemon.py b/tests/test_circadian_daemon.py
index 2fc6f81..cce7518 100644
--- a/tests/test_circadian_daemon.py
+++ b/tests/test_circadian_daemon.py
@@ -767,7 +767,40 @@ def test_bias_tick_off_out_of_window():
     d._tick_once(t)
     lw = _light_writes(d)
     assert lw["Lplay"]["on"] == {"on": False}
-    assert lw["Lcouch"]["on"] == {"on": False}      # circadian idle but out of window -> off
+    assert lw["Lcouch"]["on"] == {"on": False}      # no night_look configured -> off
+
+
+def test_bias_tick_off_out_of_window_joins_night_look():
+    # THE LIVE 2026-08-08 REPORT: with night_look configured, an idle=circadian
+    # viewing light going fully dark overnight (while the rest of the home sat
+    # at a dim night_look) read as broken, not as "TV is off" -- the only thing
+    # that should set a light apart from the rest of the home is the TV being
+    # ON, not a separate day/night schedule of its own.
+    cfg = Config.parse({
+        "bridge": {"host": "x", "application_key": "k"},
+        "location": {"lat": 45.5152, "lon": -122.6784, "tz_offset_hours": -7},
+        "motion_policies": [],
+        "circadian_daemon": {
+            "zone": "Night Guide", "interval": "60s", "transition": "75s",
+            "night_look": {"brightness": 1, "hex": "#ff0000"},
+            "bias": {
+                "lights": {
+                    "Play bars": {"look": {"mirek": 153, "brightness": 28}, "idle": "off"},
+                    "Couch": {"look": {"hex": "1a0a00", "brightness": 5}, "idle": "circadian"},
+                },
+                "triggers": {"sse": {"on_trigger": "On", "off_trigger": "Off"}},
+            },
+        },
+    })
+    d = CircadianDaemon.for_test(_FakeClient(), cfg, grouped_light_rid="GL")
+    d._bias_rids = {"Play bars": "Lplay", "Couch": "Lcouch"}
+    t = _epoch(23, 30)                 # past hand-off 22:34 -> out of window, TV off
+    d._tick_once(t)
+    lw = _light_writes(d)
+    assert lw["Lplay"]["on"] == {"on": False}       # idle=off is unaffected
+    assert lw["Lcouch"]["on"] == {"on": True}        # idle=circadian joins night_look instead
+    assert lw["Lcouch"]["dimming"] == {"brightness": 1.0}
+    assert "color" in lw["Lcouch"]
 
 
 def test_no_bias_writes_when_no_bias_configured():