The President's Mistress is a 1978 American made-for-television drama mystery film produced by Kings Road Entertainment and starring Beau Bridges, Karen Grassle, Susan Blanchard and Larry Hagman.

[1] Donna Morton has been having an affair with the President of the United States for several months, regularly meeting with him for assignations in a safe house in Washington, D.C. She is always picked up in a car by a Secret Service agent.

The same day, her brother Ben Morton – a Washington businessman and occasional courier for the CSA – arrives back in the city.

When Donna Morton is found dead in her apartment moments before she was due to be picked up by her Secret Service driver, he begins to investigate.

He tells him everything he knows – that the classified document identifying Donna Morton as a Soviet agent was a fake, designed to throw the CSA off balance, and had been intended to fall into American hands.