The Hour of 13 is a leisurely remake of the 1934 thriller The Mystery of Mr. X. The year is 1890: London is being plagued by a series of murders. The victims are all policemen, and the killer seems to be operating in a deliberate pattern. Suave jewel thief Nicholas Revel (Peter Lawford) is compelled to seek out the killer, lest he himself be accused of murder by his friendly enemy, Inspector Connor (Roland Culver). Filmed at MGM's British facilities, The Hour of 13 makes excellent use of several topnotch English supporting actors, including Dawn Addams, Derek Bond, Leslie Dwyer, Michael Hordern, and Colin Gordon. The original Mystery of Mr. X made the tactical blunder of revealing the killer's identity in the opening credits; happily, Hour of 13 does not repeat this error.