Spy's Suspicious Spouse

The Love Interest has noted something odd about her partner. He is gone at all hours, does strange things and never answers a straight question. Is he betraying her?

Never fear! Your love interest still has Undying Loyalty toward you and would never do such a thing. No, it is something else. Rather he is a great patriot bravely defending his country against The Empire. She, of course, can't be told about this because she has no need to know. So she must wonder.

Not necessarily a married couple, of course. Subtrope of Mistaken for Cheating.

Film

 * Pretty much the entire plot of True Lies is an inverted example.
 * Not spies, but close enough: Mr. and Mrs. Smith
 * The Incredibles: Mrs. Incredible gets suspicious when she finds a tear in her husband's old costume and what she thinks is Affair Hair on his suit.

Literature

 * The Scarlet Pimpernel.

Live Action TV

 * In the NCIS episode "Power Down," a young man discovers that his recently murdered wife, who he momentarily thought was cheating, was a security agent working to protect The Government against cyberattacks.
 * A subplot arc in the first season of Spooks involved the girlfriend of one of the agents adding two and two together to get five. (The time the agent went undercover as a married man and then forgot to take the ring off before he went home really didn't help.)

Truth in Television

 * This is a Real Life danger of the espionage profession.