10 TV Secrets That Were Hiding In Plain Sight

5. Wayne Williams' Cameo - Mindhunter

Mindhunter's brilliant second season culminates with Holden (Jonathan Groff) and Bill (Holt McCallany) pursuing a murderer who operated in Atlanta between 1979 and 1981, primarily preying on children.

In the season finale, suspect Wayne Williams (Christopher Livingston) is arrested for the killings, though he was ultimately only ever convicted of murdering two adults, with the city's desperate rush for closure undermining any desire to investigate him for the 23 further killings.

Williams is a focal part of season two's final two episodes, though also makes a blink-and-you'll-miss-it appearance in episode six, visible briefly as a photographer who follows the police while they investigate a tip-off.

Among the media scrum, a shot lingers on Williams' face for maybe a second, and at the time it seems completely harmless and ordinary. Two episodes later, though, Williams is brought into the story in earnest.

This ties back to discussions earlier in the season about killers returning to the scenes of their crimes, even if in this case the tip turns out to be a dud. On a rewatch, though, seeing Williams hanging around the cops sure does make the heart skip a beat.