One of the wilder premises involving a movie series was in the Crime Doctor films that starred Warner Baxter. We are asked to believe that Baxter was once gentleman crook Phil Morgan who held out the loot from his gang and who slugged him and threw him from a moving car and left him for dead. He didn't die, but has a case of amnesia. In any event ten years go by and in those ten years we are asked to believe that Baxter has acquired the eduction and training to become criminal psychologist Robert Ordway a most respected gent.
The Crime Doctor character came from radio and I assume that radio provided a lot of background so that the Ordway character became more believable. Given the fact that the movie-going public had been used to the Crime Doctor radio program the whole premise was easier to swallow in 1943 than it is today.
Baxter who is now a successful criminal psychologist and engaged to Margaret Lindsay is visited by old gang member John Litel who wants to know where the stashed loot is. He's not buying the amnesia story. He assembles the rest of the gang and the film is a battle of wits between Baxter and the rest. Need I tell you who wins?
Future Crime Doctor films gradually left out the part that Baxter was a convict and as a result they have not become as dated and are more believable than the first film. Some are actually pretty good with the simple premise that Baxter with his psychological training is a pretty good criminologist, better in many cases than those who carry a badge. In fact Jeff Goldblum's character on Law and Order: Criminal Intent who does carry a badge can trace his origins back to Warner Baxter's Robert Ordway.
A good screen character with too much unbelievable baggage.