Dr. Emmett Brown, Time Traveller
Dr. Brown is a real 'time traveller'.
The movie 'Back to the future' is actually a historical account of his
adventures through time with Dr. Birkenmeier.
However, the names and events of the actual happenings on the excursions
through time have been changed to protect the truth.
David Bowie, Flux Capasitor and Sorcerer
David Bowie is actually a very powerful sorcerer,
who accompanied Dr. Birkenmeier and Dr. Brown on their trips through time.
David Bowie is the 'Flux Capasitor' because he is so powerful he can generate 1.21 gigawatts.
The movie changed this to be a fictional device to protect David Bowie's Secret Identity.
Urkel aka The Head of the CIA
Julian the "A Pasta" aka The Flying Spaghetti Monster