Fraser returns from his vacation back in Canada to find Ray there but not there, and a copycat arsonist of a man he and Ray put away once.

When Internal Affairs thinks there are dirty cops in the department and want to grill Ray, Welsh worries about Ray's cover being blown and not being able to find him. Meanwhile Fraser, sent on the hunt for Ray, joins Ray in wait for a criminal who made Ray the man he became. Written by Gordon Will Ramsay You

Ray and Fraser blow the cover of a relocated witness set to testify in court, upsetting his brother who works for the government and looks out for him. But things may not be what they seem.

Someone attempts to kill Stanley's ex-wife Stella and her date, with Fraser and Stanley saving their lives. She's dating Frank Orsini, an alderman involved in a controversial housing project, with Fraser trying to solve the case while serving as Orsini's bodyguard.

After a man is murdered in their sight at a mall, Ray, Thatcher and Welsh argue over who did it and how, utilizing Fraser to help uncover the truth.

Tough as nails bounty hunter Janet Morse shows up while the squad is having a sick out, accompanied by her three young children. Her style attracts Benton Fraser's attention. The real problem is her quarry is also pursued by mobsters and other bounty hunters.

When the boxing opponent of a young man Ray is training is sent to the hospital possibly dead, a man turns up dead and the evidence suggests Ray's wannabe boxer may have done it.

Ray and Fraser protect an elderly ex British spy from Russian spies who are after something the old man has.

Framed for murder, Ray must stay under arrest at the Canadian consulate while Fraser goes out to hopefully solve the crime before Ray is extradited from there with an aggressive man running for the State's Attorny Office looking to put him away. Written by Gordon Will Ramsay You

One of Kowalski's informants is stabbed to death while a few days earlier a flight attendant in Canada is murdered. Fraser finds the primary suspects have airtight alibis and no obvious ties. Yet Fraser plays a hunch that there is a connection. Written by rharlan58

While Kowalski is questioning minor criminal Stanley Smith, Fraser discovers a body encased in the wall. It's Guy Rankin, who had a bad history with Francesca and she asks Fraser to find the killer but quietly. The presence of psychotic killer Kuzma and the FBI complicate matters. Written by rharlan58

Ready to split up and go their separate ways on re-assignments after a bad squabble, Ray and Fraser are drawn into one more case after a man lands on the front of Ray's car dead with a knife in his back and a map carved into his chest, leading the two into a mystery involving gold, pirates, and a ghost ship Written by Gordon Will Ramsay You

The third and fourth seasons of Due South pick up shortly after the first two left off. Fraser returns to Chicago, to find a blond has assumed Ray Vecchio's identity, and everyone just seems to accept it but him. Fraser and his new partner (real name Stanley Raymond Kowalski) soon find level ground to agree on, and work together to solve crimes on the mean streets of Chicago. Written by Kaolin