Valentine and Hardy investigate a man suspected of abusing his ex-wife when she refuses to let him have regular access to their son. However, Hardy is less than happy with Valentine's handling of the case - and openly accuses him of racism in front of the suspect, which forces Hemmingway to take him off the case. Meanwhile, Keane gets her first undercover experience when Nixon invites her to take part in an obbo to catch a callous thief posing as a security guard. However, Nixon soon finds herself trying to persuade the suspect not to make an official complaint after the heated interview turns physical, leading an irate Keane to give the suspect a slap in the face.
