An undercover operation forces Lucy and Tim to play a convincing couple, even though they can barely stand each other. The fighting is real. The tension is worse. And the longer the mission lasts, the harder it becomes to tell what's fake and what isn't.

In which Lucy and Tim go on a long-term undercover assignment...as a married couple...after their breakup. It goes as well as you'd expect. Post S6 finale Chenford fic. - "Why'd you volunteer, Tim?" Lucy asks quietly. It's the question that's been plaguing her for the past two days, ever since she saw his name on the list. There's a lot of things that Tim hates, but she's pretty sure undercover work might be at the forefront. Yet, he had volunteered to do a long-term op, posing as her husband. She knows he's trying to pay everything back to her-small doses, he had said. But... This is a lot. This isn't just some small dose. This is just about as big as a dose that anything could be. "Because," Tim starts heavily, "I'll always have your back. As long as you'll let me."