Mulder and Scully go undercover to try and gain evidence against a suspect. However, things don't go to plan and something happens to Scully. Both of their lives become endangered. Will things turn out for the best?
The M rating is for drug use and violence. Unfortunately.
There's a lull in cases so Scully volunteers herself to go undercover to catch a drug dealer/murderer, and of course Mulder has to go too. They have to push themselves to stay in character and it takes a toll, with ever-increasing angst as they put themselves in more danger.