When Beckett visits her therapist to discuss Castle's recent change in behavior, she asks what she did wrong to make him pull away. Her therapist suggests that maybe it's what she didn't do. "What if I waited too long?" she sighs.
Original Air Date: Castle Season 4, Episode 21: "Headhunters" airs on Monday, April 16, 2012 at 10 p.m. ET on ABC