For a biographical drama to work, it’s not required that the central actor do a pinpoint uncanny, so-close-to- the-real-thing-you-might-think-it’s-the-real-thing impersonation of the person he’s playing. But Peter Farrelly’s “I Play Rocky” may be a special case. It’s a movie about the making of “Rocky” — about how Sylvester Stallone, then a two-bit actor in his late 20s, dreamed it, wrote it, sold it, and insisted he play the lead role in it. Since “Rocky” is one of the most popular and beloved movies ever made, and Stallone one of the most famous stars in the history of Hollywood, it’s actually essential for the actor playing him to get it right. If not, we would just be in cheesy-tacky TV-movie land.

Anthony Ippolito, who plays Sylvester Stallone in “I Play Rocky,” gets it just right. He looks startlingly like Stallone: the droopy dark eyes, the slightly jutting lips with the delicate dip at the center, even the skin tone — that sort of peach-ivory pallor. And Ippolito’s impersonation of Stallone’s voice is a miraculous act of channeling. He gets that super-low back-of-the-throat growl, the mush-mouth intonation, the words dripping out like molasses, the sense that his whole personality is a slow-motion amiable grumble. Watching and listening to Anthony Ippolito, we can believe that Sylvester Stallone is standing right in front of us, though the performance is more than just an awesome impersonation. He’s truly playing Stallone — the sweetly stubborn and dogged person he was at the time.