In New York City, architect Michael (Gene Wilder) takes a cab with stranger Sara (Kathleen Quinlan) and is talked into mailing a package for her. But Michael doesn't know the package contains secret military documents, and, when Sara is murdered, he becomes a suspect, pursued by cops and government man Ransom (Richard Widmark). On the run, he meets Kate (Gilda Radner), whose brother's death was somehow connected to the package. She helps him evades the cops, but Ransom is harder to shake.