Movie Name ? He gets a book deal, joins a cult, they drill a hole in his leg and drugged ?

Hi,
Looking to find the name of this movie.

The main character was trying to land a book deal with a publisher and in the end he does.

And as he’s driving off in a limo the street lights go out down the road as he passes them

He ends up down and out at one point and joins a cult.
They then drill a hole in his leg and feed him drugs and they are all connected by like a leg hose.

Any help welcomed thanks.

Im thinking made early 2000’s.
Cheers.