The attempted seduction of Morse by Mrs. Richardson is almost identical to the famous scene where Mrs. Robinson first makes a move on Benjamin. Mike Nichols's film is also referenced at the end, when Peter Jakes and his girlfriend leave on a bus, like Benjamin and Elaine.
When Mrs. Richardson asks Morse, whom she is trying to seduce, if he will help her with the zipper on her dress and he, against her wishes, firmly zips it up instead of down, this is an echo of the scene between Clint Eastwood's Coogan character and a prostitute in the Don Siegel film.
The suspense sequence where Morse, trying to contact the kidnapper with the money, must run from one public phone booth to another in very short time, is almost identical to the famous sequence where Harry Callahan delivers ransom money to Scorpio in Don Siegel's film.