Plot hole: "Dorothy Michaels" does not exist, but suddenly becomes famous. It is simply not feasible that nobody looks into her background! Not one single print or television reporter is interested in her life story? Nobody has ever wondered where she came from, has checked into what other roles she had played, or has expressed interest in her personal life? That's impossible.
Plot hole: Since "Dorothy Michaels" does not exist, she will not have a Social Security number. Even with her agent acting as a go-between, the television production company, her employers, would have to have this for their records. Supplying a false Social Security number is a very serious offense (and is instantly detectable), as is employing someone without one.
Plot hole: Michael Dorsey is a jobbing actor working as a kitchen hand, and his flatmate Geoff is an aspiring writer trying to raise the capital to have his latest play on stage - yet they can afford a huge, open plan apartment in New York City. The rent on that apartment would easily exceed their combined income from their low-paying jobs. There is no indication that they are independently wealthy - why would they need Dorsey's fees from the soap opera to stage Geoff's play if they were?
Answer: No I believe that's from the movie.