The original stage production of "Sleuth", by Anthony Shaffer, opened on Broadway on November 12, 1970. It originally starred Sir Anthony Quayle as Andrew and Keith Baxter as Milo, ran for 1,222 performances, and won the 1971 Tony Award for Best Play.
(At around thirty-one minutes) At one point in the movie, Milo asks Andrew "What's it all about?" This was the tagline of Alfie (1966) and Alfie (2004), which respectively starred Sir Michael Caine and Jude Law in the title role.
Milo Tindle (Jude Law) states near the end that he's never been to Coney Island. Another of Law's characters, Gigolo Joe from A.I. Artificial Intelligence (2001), almost got there with his friend David, but was captured shortly before they arrived.