My wife was watching this 1949 film noir called Tension on one of those retro channels the other day. I looked this film up at IMDb, and there is interesting H50 trivia connected with this show:

The four main actors in this movie (as IDd on the poster at IMDb) all appeared on Five-O:

Richard Basehart - Murdock, The Odd Lot Caper
Audrey Totter - Mrs. Royce, Draw Me A Killer
Cyd Charisse - Alicia Warren, Death Mask
Barry Sullivan - Morgan Hilliard, While You're at It, Bring in the Moon

Not only that, Lloyd Gough, another actor in the film, played Nelson Blake, the father in The Ransom!