The F.B.I. (1965) : 8x15

Hitman Stuart Tilden seriously wounds a businessman in Chicago while seeking the whereabouts of his intended target. The FBI launches an intense investigation, seeking to prevent him from succeeding, and even Assistant Director Arthur Ward will make an arrest in the field as part of the effort. The target is Richard Ghormley, who formerly worked for a criminal. While he wasn't involved with illegal activities, the criminal fears that he knows too much. He is desperately trying to get home from a business trip to San Francisco on Christmas Eve and Tilden is waiting for him there. Colby and other agents rescue his children while Erskine confronts Tilden.