Tang (special guest star Lucy Liu) tries to help a homeless vet get an ID so he will be admitted to the homeless shelter. The situation opens John's eyes to his partner's past. Sammy is determined to save a dog after he accidentally shoots it in the leg. Lydia and Ruben (guest star Dorian Missick) investigate the murder of a man who lent a helping hand to women in need. And Ben and Lydia each face big life changes.