Karen Boyer is a character in the 1985 comedy film "Spies Like Us." She is played by actress Donna Dixon. Karen is a beautiful and intelligent Russian agent who is assigned to work with Emmett Fitz-Hume (Chevy Chase) and Austin Millbarge (Dan Aykroyd), two bumbling American government employees who are sent to the Soviet Union as decoy spies.

At first, Karen is suspicious of Emmett and Austin's qualifications as spies, but she eventually becomes sympathetic to their situation and begins to help them complete their mission. Throughout the film, Karen displays her intelligence and resourcefulness, and she proves to be a valuable ally to Emmett and Austin.

Karen also becomes romantically involved with Emmett, and the two share a number of comedic moments throughout the film. Their relationship provides a contrast to the tense political situation between the United States and the Soviet Union.

Overall, Karen Boyer is an important character in "Spies Like Us," and she contributes to the film's comedic tone and plot. Her intelligence and charm make her a memorable character in the movie.