Visible crew/equipment: When the gust of wind blows into Helen's temple, the shadow of the giant fan creating the effect is seen.
Kolchak: The Night Stalker (1974)
1 visible crew/equipment mistake in The Youth Killer - chronological order
Starring: Darren McGavin, Simon Oakland, Jack Grinnage, Ruth McDevitt
They Have Been, They Are, They Will Be... - S1-E3
Continuity mistake: While Tony Vincenzo is eating, his butter knife instantly turns into a fork in the next shot.
Coach Toomey: Actually, Burdett never made the team.
Carl Kolchak: No?
Coach Toomey: You see, his butterfly stroke was like an effeminate moth.
Trivia: Lara Parker, who plays Madelaine the witch in this episode, also played Angelique, the witch in the TV series, "Dark Shadows."