Kate Beckett's investigation into her mother's death is reactivated when Hal Lockwood - a professional hitman with knowledge of Beckett's mother's murder - stages a spectacular escape during a court hearing. As police launch a manhunt for Lockwood, Castle and the team uncover evidence of a deeper conspiracy involving a mysterious figure with law enforcement connections who is linked to both Lockwood's escape and the killing of Johanna Beckett. The search for Lockwood and the quest to identify his co-conspirator leads to a shocking and deadly conclusion.