The film was originally intended as a vehicle for both Richard Dreyfuss and Elliott Gould, but both dropped out of the project before production began.
Director Nicholas Meyer was reputedly so annoyed at the studio's interference with this film's East vs West plot, that he recycled it on his next film, Star Trek VI: The Undiscovered Country (1991).
When Boyd and Grushenko jump from the window into the lake, Grushenko leaves the window first. In the next shot, as they are falling, Grushenko is leading. But, when they hit the water, Boyd hits the water first.
When they climb out of the lake after jumping from the apartment window, Grushenko's clothes are soaking wet but his hair is completely dry and in place.