Middle Man

Lenny Freeman is a straight-laced old-school accountant with a dream; to become a famous stand-up comedian. The problem is he's not very funny. Not even close. When his mother dies, leaving him nothing but debt and her '53 Oldsmobile
When a hapless, unfunny, wanna-be comedian picks up a mysterious hitchhiker on his way to Vegas to audition for the Monte Guy show, he unwittingly becomes trapped in a desert-town killing spree that also has a very unexpected consequence - it improves his comedy.