Six months after the shooting of Des Courtney, the Doyles are at a graveyard mass when Mal's estranged brother-in-law (Angus Macfadyen) arrives in desperate need of help. It turns out his son, Rory (Martin McCann), has fled to St. John's after getting himself in trouble with some gangsters back in Dublin, and he needs the Doyles to find him before the wrong people do. But when Jake finally does track Rory down, he finds himself becoming an accomplice in Rory's armed robbery of an underground casino. Now that Rory has even more gangsters after him, Jake has to figure out what his cousin is really up to; all while Mal wrestles with his longstanding resentment of his brother-in-law, stemming from something that happened when Jake's mother passed away. Amongst the family drama, Jake goes to the police station to talk to Leslie, only to find that her desk has been cleared out. In her place: Constable Monica Hayward who has done her research on Jake and is not sure if he's trouble - Jake could say the same about her. Tinny, meanwhile, is helping to surprise Jake with a very special gift.
Jake and Mal are given no choice but to help an escaped convict prove his innocence, and they get a glimpse of the drug trade in the city in the bargain; Tinny's curiosity about her father grows; Jake finds out why Leslie's been off the radar.
Jake and Mal are hired by a man to find his wife, who he claims is alive and well despite being reported dead for years; Tinny takes her investigation into Crocker a step further; Leslie embraces Jake as a confidante.
After a ransom drop goes bad, Jake and Mal fight against the clock and an unpredictable man to find the location of a kidnapped girl; Tinny shares some shocking news; Leslie slips deeper into her risky assignment.
Jake's worst fears are realized upon discovery that Leslie has gone missing while working her dangerous undercover assignment, and now he's determined to find her at all costs. Meanwhile, an unlikely and suspicious client enlists Des's PI services.
The Doyles are hot on the trail of an international art thief; Constable Hayward makes a grave mistake with career-impacting implications; Leslie struggles as she deals with an important family issue.
Jake rushes to Leslie's side when the death of her father takes them to her hometown of Brigus, where a time of mourning turns into a full-fledged Doyle-style investigation when the death is ruled suspicious; Crocker formulates a plot to keep from being transferred to Vancouver.
Jake finds himself juggling multiple cases while looking into attempts made on the life of his ex-girlfriend; Tinny's relationship with her Uncle Jake is becoming strained due to her budding relationship with her father.
When Jake is kidnapped and nearly burned alive, he escapes and teams up with Mal to track down his would-be killers and make sense of the whispers that a mysterious "boss" is behind the plot; Monica builds a case against Jake and ropes Tinny into it.
Mal and Rose try to keep an old friend safe and find out what kind of business he’s really into. Jake is laid up with a bad injury and his medication causes some strange dreams.
When a crazed bomber takes over the police station, it's up to Jake to try and diffuse the situation from the inside before the hostage crisis can turn fatal; Trapped outside, Leslie leads the RNC command post with Jake's life hanging in the balance.
The city is thrown into chaos when a prison break floods the streets with escaped cons, and a threat against Tinny makes it extremely personal for Jake; Unfazed by the warnings from her uncle and grandfather, Tinny oversees a police transport of seized guns and drugs.
With Tinny abducted at gunpoint by Maurice Becker, Jake and Crocker have no choice but to work together to get her back. While being held captive, Tinny attempts to get into Becker's head.