There was almost a (terrible) Godfather reunion that would have made Caan a fair, curly-haired Superman. What Happened? This revelation only came to light fairly recently, when Caan spoke to Howard Stern about roles that he had missed out on or rejected. In between dismissing Harrison Ford as "not an actor," based on some vague personal beef with the Han Solo star, Caan confirmed that he had been offered the lead role in the Mario Puzo scripted Superman that pre-dated Christopher Reeve's casting. And though the appeal might have been hard to resist in other circumstances, Caan also confirmed the reason he turned it down. It was too silly:
"When Clark Kent is just devastated cause she (Lois Lane) is so in love with Superman. Physically the office is setup in the paper (Daily Planet)... In order to get to Clark Kent's office you must pass through Lois Lane's office. So, there is no other way in. So, one day Clark is so pissed off (laughs) that she is in love with Superman, he says, aw screw it. And he rips his clothes off and he's got his Superman thing (costume) on under there. And he says, "Lois, come in here!" She comes in and looks at him, "That's sweet Clark, but you're no Superman." And she walks out. He looks and the mirror and says, "Maybe a little tuck here." It was all tongue-in-cheek."
Would He Have Worked? He might have in a different film, but not in the one he says was offered to him. He could also have been a great Lex Luthor.