Detective Frank Drebin (Leslie Nielsen) tries to uncover a plan to assassinate Queen Elizabeth II, who is on a state visit to the USA. The main suspect is Vincent Ludwig, a rich businessman (Ricardo Montalbán), who uses a hypnotic device to turn others into murderers. As with previous ZAZ spoof comedies, the plot was mostly culled from another—more serious—movie. In this case, it was Telefon wherein people were triggered into assassins via hypnotic phone calls (indeed, dialogue in the post-hypnotic suggestion demonstration scene is copied word-for-word from Telefon).
On the case, Drebin falls in love with Ludwig's assistant, Jane Spencer (Priscilla Presley). She knows nothing about Ludwig's plot, and after the pair spend the night together, Jane helps with Frank's investigation.