A doctor trying to fight a diphtheria epidemic comes into conflict with a police captain who is using all his resources to track down a cop-killer.
| Actor | Role |
|---|---|
 Robert WagnerDr. Larry Ross | Dr. Larry Ross |
 Diane BakerTracey Morrow | Tracey Morrow |
 Greg MorrisCapt. George Benson | Capt. George Benson |
 Theodore BikelSgt. Phl 'Sharkey' Gold | Sgt. Phl 'Sharkey' Gold |
 Robert LansingWarren Claman | Warren Claman |
 Mercedes McCambridgeSister Sarah | Sister Sarah |
 Pedro Armendáriz Jr.Dr. Carlos Madera | Dr. Carlos Madera |
 Mike EvansMarley | Marley |
 Robert CornthwaiteDr. Bradville | Dr. Bradville |