old movie serials

I am not sure if you mean the Saturday morning matinee cliffhanger serials or movie series. The cliffhangers, which usually had 12 to 15 chapters of about 15 minutes each, were seen on a weekly basis. Often the studios would take these action films and cut them down (using material from the first and last few chapters) into a 60-90 minute feature. For example, Republic’s 1938 12-chapter Tarzan rip-off serial “Hawk of the Wilderness” (3 hours 35 minutes total runtime) was reissued in 1966 as a 100 minute feature called “Lost Island of Kioga.”

On the other hand, series were individual stories, usually low-budget, that had continuing characters. These petered out in the 1950s as they were replaced by weekly TV. Only James Bond still exists as a true film series. I don’t count the multiple “sequel” films of today.

You mention The Lone Wolf and Crime Doctor.

Michael Lanyard (aka The Lone Wolf), a former jewel thief turned good detective but always suspected by the police of still plying his trade (see also Raffles and The Saint) appeared in a series of eight books beginning in 1914. Movies picked up the character in 1917 and Lone Wolf films continued through the classic period. From 1939 to 1943, Warren William played Lanyard in eight films at Columbia.

Crime Doctor was a 10-picture series taken from a weekly radio drama. Oscar winner Warner Baxter played the crime solving Dr. Ordway in all of them. The series was in production from 1943 to 1949.

I’ve never seen any of the seven “Mexican Spitfire” films that ran from 1939 to 1943 nor the four “Five Little Peppers” (based on books). I had never even heard of “Scattergood Baines” (five movies) before this.

I am not aware of one of these “series” films ever being combined with a second to result in a third.

Hope I didn’t give more information than necessary.