It all started with a red editor's pen after a night of whiskey and remorse. The pig standing behind her, breathing his hot stink down the nape of her neck, had harassed her for the last time. As the ballpoint punctured his inner thigh, she knew her career was over.
Norah Blythe thinks she's paying penance when she takes an assignment to write a piece on the local asylum, slated to run front page. Only in her first interview does she learn she was a victim of a scam, tricked into enrolling as a patient and stuck there until the lead doctor deems her fit to leave. Now she must convince the staff of Shady Oaks that she's sane, write something Pulitzer-worthy to save her job and make it home in time to snare Jack Strong, the sexy bartender who's been dancing the flamenco on her heart since her fiance left her. Only problem is, she may not be sane. Nobody Girl is 50,000 words.
Well you've got schizophrenic tone all right. You sound like chick lit half the time, and then "she may not be sane" pulls us right out of that voice and into the rose garden you never promised.
The only way this works is if you're writing from her delusional point of view in places or all places and the reader comes to realize that. There's no way to convey that in hook other than just saying so.
If she's not delusional and in fact just "undercover" then the signed herself in and she can get out any time she wants to. If nowhere else, we all learned that from Ken Kesey.