An FBI agent, part of the White Collar Crime division, winds up getting a civilian caught in the crossfire. The man winds up in a coma, but the agent begins to think she is going mad as the ghost of the man haunts her as she continues to work. This is until the "ghost" takes a bullet for her, halting it in its tracks. She then begins to listen to the advice he offers her, through various psychic abilities he is starting to develop. But, just as the agent is starting to rely on his advice to solve her cases quickly and cleanly, things become complicated when her "ghost" wakes back up.

I'm just fine with doing skeleton character sheets for this story, although I might throw in a little bit of personality mixed with history, just to fully establish his character in my head.  You don't have to, though, if you don't want to.