Film producer Bobby Bowfinger (Steve Martin) is extremely eager to make a film, he's saved up for it his entire life he now has $2,184 to pay for production costs. With a script ('Chubby Rain') penned by an accountant (Adam Alexi-Malle), a camera operator (Jamie Kennedy) with access to studio-owned equipment, and several actors who are hungry for work (Christine Baranski, Heather Graham, Kohl Sudduth) he needs access to a studio in order to distribute his masterwork.
He manages to extract a promise from a film studio executive (Robert Downey Jr.) that the executive will distribute the film if it includes currently-hot action star Kit Ramsey (Eddie Murphy). Ramsey - a rather pompous, neurotic actor - refuses, so Bowfinger constructs a plan to covertly film (on an extremely low budget) all of Ramsey's scenes without his knowledge. The actors, told that Ramsey is method acting and will not be interacting with them outside of their scenes, walk up to Ramsey in public and recite their lines while hidden cameras catch Ramsey's confused reactions.
The plan goes well at first. Ramsey ends up starring (unknowingly) in the movie. However, Ramsey (who is a member of an organization called MindHead) misinterprets the movie's sci-fi dialogue and believes he's being stalked by aliens, damaging his already-precarious mental state. He finally goes into hiding in order to maintain his sanity. This puts a hold on the film production, and leaves Bowfinger wondering what to do next.
A desperate Bowfinger resorts to hiring a Ramsey lookalike (also played by Murphy) named Jiff. Jiff is kind, amiable and rather clueless. He even runs a gauntlet of 'stunt drivers' racing along a major freeway when asked. Eventually, he becomes depressed about his lack of acting talent, but another cast member assures him that his real talent is being an exact double for Kit Ramsey. Jiff isn't sure 'how much of a talent that is...I mean, I am his brothe