Picture, if you will, a screenplay.
Written by Charles Band, as a big-screen adaptation of Marvel Comics’ Sorceror Supreme, Doctor Stephen Strange.
It sat on the shelf in development hell for years, during which time the licence to use the Dr. Strange character expired.

Doctor Stephen Strange

Doctor Strange

Fast forward, to 1992, when the script was dusted off, rewritten by C. Courtney Joyner, and packaged as a vehicle for “Re-animator” icon, Jeffrey Combs.
Enter, “Doctor Mordrid.” [Trailer below]

Ignore the cheesy special FX, the fact that Mordrid doesn’t have a moustache, squint a little, and you’ll see a more than passing resemblance, between the two good Doctors.

In a similar vein, you know The CW’s “Smallville” – now entering its 10th and final season, as it charts the transition of young CLark Kent from brash farm boy, to Man of Steel?

Originally, the show was conceived as “The Young Bruce Wayne Chronicles” – until legal constraints made it impossible for the Batman universe to be translated to the small screen.

I can think of a slightly different case.
One where two separate movies were made, using the same basic premise: A Mob fixer applies pressure on a jury member Рa plucky  but extortable single mom Рto force a mistrial in the prosecution of a major gangster.
Both films had a central villain with the same name.

In “Trial By Jury” [1994], Joanne Whalley-Kilmer was the mom, pressured by corrupt cop William Hurt – who refers to himself as The Teacher.

Trial By Jury trailer

In “The Juror” [1996], juror (duh!) Demi Moore comes under the influence of psycho fixer Alec Baldwin – a man known only as The Teacher.

Any others out there, that you can think of?