When you work with someone for years, you think you know them pretty well. Casey Wicker and Martin Bishop are a British Secret Service team with a reputation for ignoring rules but delivering results. They've also built a tight friendship, with more than a spark of unspoken attraction. While on assignment to Scotland Yard, Martin rescues Casey and exposes him to a life-changing secret. Martin is not what he seems, and now that Casey is aware of that, the knowledge most likely comes with a death sentence. When a way to avoid the tragic ending is suggested, it may very well take more cooperation than anyone is willing to expend.