the true story behind Goodfellas is one that surprised me because of how insane it was (and Goodfellas as a film was already pretty over-the-top). For example, the real Tommy, unlike Pesci, was like 6'4 and looked like a movie star. Both him and the real-life Jimmy were a lot more sadistic, cruel and killed more people IRL than they did in the film. there was just A LOT that the film left out that they could've added. I actually think a biopic focusing on either Jimmy or Tommy specifically has enough material for it's own film (Henry Hill was actually the least interesting person in Goodfellas story).