Lenny Montana (right), who played enforcer Luca Brasi, was a professional wrestler and, more interestingly, an associate of the Colombo crime family in real life. It was Montana's connection to the family, in fact, that helped him get the role.

Montana, appearing in his first film, was extremely nervous on set — especially opposite the great Marlon Brando (left). When director Francis Ford Coppola saw Montana repeatedly practicing his lines, he wrote that into the film. (Before Brasi speaks with Vito Corleone at the wedding, he continually rehearses what he's going to say to the don.)

Then, when filming the scene with Brando, Montana experienced extreme nerves and struggled to get his words out. Coppola loved it and kept it in the film.