Chris Watts killed his pregnant wife and two young children and buried them in a tank. This mini-documentary by Jim Can't Swim (patreon) takes us through the bodycam footage of a cop called to his house after Shannon Watts failed to turn up to a rendezvous with a friend, and subsequent interview with detectives. It's detailed and striking work, pointing out the subtle (and not so subtle) tells in his calm behavior that led the police to suspect he was the culprit. You can tell why no-one knew what he'd done, but can readily see they felt it from the outset.
We are rightfully armed by reason against such feelings as they are often wrong. Nonetheless, there's a moment in the bodycam video where Shanann Watts' friend makes a certain facial expression after Chris arrives home but doesn't call for his wife. You can't say it's realization, but she's sinking fast.