A2Lights out, one source left
Even overheads → one warm pool
Penlight beam → cold flat fluorescent
A1b

Medium shot of a young woman detective in a dark coat searching a suspect's office at night with a small penlight, photoreal thriller, locked camera. 0–2s: the office is pitch dark; only the narrow penlight beam lights her face and an open desk drawer. 2–4s: the overhead fluorescent lights snap on with a hard flicker. 4–6s: harsh, bright, flat white light floods the whole office, every corner exposed, her face suddenly bright and pale. 6–8s: she freezes in the glare, penlight still raised, and slowly looks toward the door out of frame. Throughout: filing cabinets, blinds over a dark window, high-key white light after the switch, fixed camera, one continuous take.
Same layer as the comedy version; only the subject, the cold color and the stakes changed. Exposure reads as danger instead of a joke.
Same light, other genre: Lights on (caught)
A2Even overheads → one warm pool
A3Clean white → pulsing crimson
A4Steady green → stutter → dryer glow