After seeing this movie for the first time, Sir Michael Caine wrote writer and director Paolo Sorrentino a letter, saying he was deeply touched, and he described how, during the trip back home in the taxi with his wife, he kept on crying.
Jane Fonda became interested in the role of Brenda, after friend Al Pacino had told her that the part was "written for you". Another actress had been cast, but dropped out, and so Fonda had her agent secure the role on her behalf.
Sir Michael Caine was given dark-framed glasses to wear "because they would make my hair appear to be whiter."
When Michael Caine and Harvey Keitel are relaxing in the pool and when suddenly a nude Miss Universe appears they react with disbelief but are of course also very agreeable surprised. But according to Michael Caine director Sorrento didn't tell them she was going to appear completely naked. So the surprise on their faces is for real. The scene also made the official movie poster.