Castle: Hayley's past uncovered

Can Castle and Beckett actually trust the woman they’ve been working with all season? That question will be raised during Monday’s episode of Castle, when Hayley (Toks Olagundoye) is implicated in a killing and cyber-terror attack, forcing Beckett (Stana Katic) and Castle (Nathan Fillion) to solve the case and clear her name.

“We thought it would be exciting to dig into the mystery of who this woman is, because there’s a lot of layers,” says executive producer Alexi Hawley. “As we saw in episode 4, she has a history with MI6, so we thought we would dive into that. It starts off with her being involved in a little extra curricular activity outside of the Castle P.I. thing, which ends up getting her connected to a murder.”

Suffice it to say, secrets are revealed that challenge the team’s trust in her. “By the end of the episode, we actually learn a little bit more about Hayley and who she was versus who she is now,” EP Terence Paul Winter adds. “There’s some emotional moments in there that are really quite dynamic.”

Castle airs Mondays at 10 p.m. ET on ABC.