It's a race against the clock as Dov and Gail work under Swarek's expert tutelage in a stakeout operation to stop an Asian gang from killing a snitch. Meanwhile, at Mounted Unit training day, Andy and Chris join the rookies from 27 Division in a competitive equine training event that gets Andy back in the saddle—both personally and professionally.

Andy, Dov and Traci are tested with a challenging undercover training exercise, but things go awry when Andy and Traci run into Swarek on his own undercover operation, and they must tread carefully not to blow his cover. The women stumble on a young woman who is overdosing and risk blowing their own cover to save her life. Meanwhile, Dov finds himself on a "ride-along" with a drug dealer who was an old friend of his dead brother's, and faces a choice that could threaten his career. Back at the station, Chris and Gail deal with a teenage boy they found tied up at a graveyard, but must sift through the wreckage of their relationship to get to the bottom of a bullying situation.