Todd Russell’s review published on Letterboxd:
The film that started it all, the one, the only, written and starred by Sylvester Stallone as Rocky "The Italian Stallion" Balboa, a southpaw picked by the heavyweight champion, Apollo Creed for a once in a lifetime shot at the title. The boxing takes a backseat to an even more gratifying character and romance drama. There are so many angles to this underdog film that it appeals on multiple levels.
Filmed on a shoestring budget and yet it has everything you could ever want in a great film: compelling story, great characters, conflict, drama, love and action. It's strange looking back 40+ years later and Stallone hasn't written anything better. Sure, he has starred in some great movies, but his writing and acting performance here is a classic.
(Sidenote: I took away a half star because this story seemed to be based on or at least largely inspired by the true story of boxer Chuck Wepner, although Wepner never got any credit or money for it. Wepner's true life boxing story is different enough from Rocky, but still there is controversy here that slightly mars the true origins of the film for me. If you want to learn more about Wepner, see the film Chuck [2016])