The incident in which Alfred Molina's character slaps Mike Malloy's with a sword during a performance is based on a real-life incident in which actor Nicol Williamson struck a fellow actor on the buttocks with a sword during a performance of "I Hate Hamlet." Williamson also exemplified his disdain for the play and his cast mates by breaking character and badmouthing the material on and off stage.
Stanley Tucci and Oliver Platt first met at Yale University where they developed the characters of the two unemployed actors that they play in this film.
When Arthur puts his giant martini down on the counter, Happy can be seen in the background pulling it towards him. A second later when he and Emily are seen from the front talking, the martini glass is nowhere to be seen. It is too large to not be in the shot.
Maurice: [mocking Burtom]
He has blustered his way to success on the backs of the great supporting players for too long and it's time for us to make a stand and say: 'No, no, Burtom! Be gone!' It is time for us to say: 'No, boozy boy! Bye bye, Burtom, bad boy! Have at thee boy! Boozy, boozy boy! Greasy boy! Saggy farty boy! I poke you! I poke you! I poke you!' Something like that.