Sergeant Jake Doyle is assigned to protect a mob informant but when a mysterious group of men impede him, Jake finds the tables turned - himself the target of a manhunt.

The Doyles struggle to prove Mal's innocence when he's accused of murder, but end up digging a deeper hole; Kathleen gets some brotherly help with the George situation; Tinny discovers the identity of her father.

It's a trip down memory lane as the Doyles investigate the murder of an old client. But when the body count rises, Jake starts to question the whole case. Rose gets in hot water with the police and Des's budding romance with med student Chandra begins to rub Tinny the wrong way.

Jake is hired to retrieve a priceless violin from a familiar con artist; Mal continues to dig into the death of his former partner; Kathleen is roped into another of George’s schemes.

When Des finds himself in a very bizarre and compromising position, the Doyle clan works overtime to get him off the hook; Jake meets someone who has been complicating Allison's life; Tinny and Des start coming to terms with their feelings for each other.

When Tinny and Des are snatched from the safety of the Doyle home in broad daylight, Jake is forced to confront a dangerous man from his past (Paul Gross) to get them back; Leslie loses something else very precious to her; Jake makes a decision about his future with Allison.

Jake and Mal investigate a hit-and-run and encounter a slippery criminal couple; Rose has a run-in with familiar ghosts from her past; Des discovers that Tinny's trip to London didn't go as expected. Guest star: Shannon Tweed

The Doyles are hired to recover a missing item belonging to a beautiful client; Nikki asks Jake a favour he wants nothing to do with; Tinny enlists Des in keeping a secret.

When Des's dad is kidnapped after being released from jail, the Doyles must band together and save Jody Redmond before it's too late; Mal is distracted when he gets bad news about his old partner; Kathleen angers Tinny when she chooses an issue from the past over a case from the present.

When an old Doyle family friend accidentally goes missing at sea, the Doyles are hired by his daughter to find out what really happened; Jake is forced to bail out Christian and picks up another line of business and a pile of new debt.

The Doyles reluctantly take on a case from a dodgy "old friend" when he promises them a big payday; Jake and Allison encounter friction when their professional lives impose on their personal relationship; Jake gets an interesting job offer from an unlikely source.

Jake buys an expensive gift for Allison only to have it stolen by a thief; The Mayor finds himself in a compromising position and asks for Jake's help and his silence; Mal has trouble telling a lie to his kids; Leslie thinks she's being followed.

Jake and Leslie find themselves trapped while trying to stop a robbery in progress; When Mal discovers his son is missing, he and Des try to locate Jake before it's too late; Rose helps newly-returned Doyle daughter, Kathleen, with a problem from her past.

Stuck in Her Majesty's Penitentiary, Jake's only chance of freedom lies in the capture of a wanted kidnapper; Mal and Rose investigate a case that hits close to home; Walter helps Kathleen with a parenting issue.

With the infamous Maurice Becker back in town, Jake Doyle must get to the bottom of Maurice's fabrications before he disappears again; a Quebec cop makes Leslie think twice about her single status; Des attempts to rebound after his break-up with Chandra.

In order to find out where some stolen goods are, Jake gets himself arrested in order to be jailed with the thief who knows the location; Mal finds out some information about Rose that she's been keeping hidden from him.

It's matrimony -- Doyle style -- as Jake and Mal are tasked with finding the person responsible for sabotaging an upcoming wedding; Mal and Rose fix a bump in the road in their relationship as Jake and Allison hit a stride in theirs; Des comes to Tinny's rescue but ends up exploding her plans in the process.

Crime novelist Garrison Steele returns again to both hire and torment Jake to help him research a murder case; Jake and Leslie struggle to keep their mutual affection for each other in check; Allison receives some much-needed help from Jake.

The Doyles are hired by a real estate agent to investigate a series of strange occurrences at the site of her controversial housing development; Leslie uncovers some suspicious facts about the Mayor; the tension between Jake and the Mayor hits a high point; Allison makes Jake a serious proposition.

Novelist Garrison Steele returns, hiring the Doyles to track down the love of his life. On the homefront, the Doyles get a new houseguest who's not planning on leaving any time soon. Jake dodges his ex-wife Nikki while wooing his ex-girlfriend Leslie - who'll have none of it.

As one member of a biased jury, Jake struggles to exonerate an innocent woman; Des uses his skills to assist Jake's investigation on the outside; A decision from Kathleen’s past puts the Doyles in danger.

It's no laughing matter when a comedian is being stalked, and the Doyles are on the case to find the stalker; Jake gets some inside info on Allison.

When a member of the Doyle clan is in danger from both the police and a killer, the family comes together to stay safe.

A new case gets Jake and Mal caught in the middle of a daylight-kidnapping gang, which they quickly discover is all just a game. The game takes a sinister turn when one of the players turns up dead, and it's up to the Doyle P.I. Agency to find the killer in a very real murder. Des practises his investigative skills by tailing Tinny and finds out some very disturbing information.

Jake and Mal are called to check into some death threats that have been made to a respected psychiatrist; an old "friend" from the past shows up and makes an interesting proposition to the Doyles; after Leslie's close call, Jake and Leslie find themselves struggling a little in their new romantic relationships.