Ali and Inspector Ross return to the Squad room in formal dress, their conversation indicating that Ali accompanied Ross on an official function, but there is indication that Ross is interested in her. Meanwhile, Logozzo has turned up some evidence of an old murder and the victim leads to a disappearance of Rev. Douglas Somerset. Somerset had left to go on mission trip in his own plane, but the plane never took off. Speculation is that Somerset was murdered by a hooker. The odd thing was that once the family had reported the missing man, they never checked back to see if the police had turned up anything. The circumstances of the man's disappearance causes Ali to think about the loss of her father, a pilot, in a plane crash. His body was never recovered.

Two robbery suspects take hostages in the squad room.

Christopher Gerald Williams was ten when he was taken from the bedroom he shared with his seven-year-old brother Joey in 1977. Twenty years later when another body is found, Tony realises that David Sawyer was killed in a way very similar to young Christopher, and Ali joins forces with Iredell to uncover the killer. After doing DNA tests, the squad realises that the same man killed both boys, and they begin investigating Victor de Jarre and Jacob Knewling, who were suspects in the first investigation. Ali tries to get what she can out of Christopher's now-grown brother Joey, who has become an alcoholic.

A social worker brings Ali in on an a case of possible child abuse. Ali protests that it's out of her jurisdiction, but the same couple lost another child to an ""accident"" a couple of years before that could have been abuse. Bobby Johnson is a cold file. As the investigation proceeds, the relationship between Ali and Inspector Ross heats up and Ali learns that he is divorced. She also has to discover there's a fine line between business and personal issues and she's confused.

Ali and Frank are assigned to find out who murdered plastic surgeon Marvin Michaelsen after a drug dealer identifies him as the man who removed his fingerprints, but the tension between the two soon ends up taking a higher priority than the investigation. Nicco and Mickey work together on the case of Dermot Wells, a garbage collector that is believed to have murdered his former co-worker, and make a bet on how soon they'll get a confession.

The murder of gay-basher Ken Reegan on Davies street prompts the squad to re-open the three-year-old murder of another gay-basher, Terrance 'Tron' McLean. Nicco and Len connect with homicide to investigate the case, and Len can't keep his personal prejudices out of the case, which involve working with a gay officer, Luke Darling. Mickey uses the department's new computer toy to help Ali with a 10-year-old arson case. It eventually leads Ali to Boris Delgado, a former troublemaker who found religion after the first fire but was unable to escape his past.

After Mitchell Huston dies under mysterious circumstances at the Green Abbey hospice, Father Geddes points the finger at Dr. Sarah MacInnis. MacInnis ends up arrested, and Maz tells Ali he thinks they have an open and shut case, especially now that they also suspect Sarah of killing her husband Gavin (Mac) years earlier. Ross keeps trying to get Ali to move on the Seniuk case, and even though Tony learns that the real Nancy Seniuk was born in 1922 and died two years later, Ali lies to Ross when he asks her about it. She also suspects his motives after Malcolm, who sees them having dinner together, warns her against romance in the workplace.

Ali and Frank investigate a rock star accused of murdering a woman who fathered his child -- a woman he swears he never even met. While trying to figure out what Nicco does with his time, Mickey investigates the case of a woman who comes in and tells them her husband killed a baby.

A count of the corpses in storage at a police training facility leads to a murder investigation.

The squad helps Moscow police probe a Russian hockey star's death.

Harper can't let go of his obsession with Viveca Wells. He is convinced that she murdered her last husband, and when he learns she's engaged to be married again, he tries to warn her fiancé, Richard, who tells Harper that he knows all about her past, and he's okay with it. While researching the case with Ali and trying to fight his own attraction to Wells, he learns that Richard has been the man in her life all along. Nicco is upset because in the six weeks since he's been off of suspension, he hasn't worked a single case. Ali finally throws him a bone by having him interview a prospective witness in the case of a racially motivated murder and while Nicco gets the man to ID the suspect, he's not happy with it.

The Cold Squad uncovers a link between the gruesome murder and decapitation of two nurses committed more than 20 years ago. (source: http://www.coldsquad.com)

After Sandy Kilkenny is arrested for tossing a pool cue at her husband's head, the squad brings her in hoping that they can finally put to rest the murder of Rita Brice eight years ago. Unfortunately, even though Ali goes undercover in a cell with Sandy, she refuses to implicate her husband, even though everyone tries to tell her that Neil Brice is no good.

Four years earlier, Rikki Stanfield lied to Ali about what she remembered the night that she and her best friend, Michelle Dorn, were attacked to get Ali to leave her alone. When Rikki starts to remember what really happened she begs Ali to re-open the case, and despite Logozzo's feeling that Rikki is a few bricks short of a load, Ali takes on the case.

Ali and Logozzo investigate the case of Stephanie Jordan, a debutante who disappeared four years earlier and was presumed, but never proven, to be dead. Her husband, reporter Turner Jordan, is their prime suspect, and he puts a serious crick in the investigation by making a televised plea for anyone with information to phone the police. Logozzo is frustrated because his daughter from his first marriage is not only getting married outdoors, she has invited his third ex-wife Vivian, with whom Logozzo does not get along.

It's almost Logozzo's birthday and a contact, Buzz, who shares the date, shows up with a tip for Logozzo that may help solve a cold file on a truck driver who was murdered while trying to rape a young woman. The key witness, the woman, was drunk and emotionally disturbed. Ali learns she is now married and has found religion. But she is unwilling to help. (Detailed recap available.)

mickey stumbles across a potential lead in an investigation that had been leading the squad to a dead end in there investigation.

Twelve years ago, a teenaged girl named Janine Elston was shot while she slept in her bed. Her father, a former cop, goes to Cold Squad to ask for help when Wayne Corby, the man who was believed to have killed her, is about to be released from jail. Since Corby was never charged with Janine's death, he could still be held responsible.

Nicco and Ali investigate the unsolved murder of Jeff Steeves, AKA. Vulse G, after a car is found underwater. The car leads them to an elderly woman named Clarice Fry, which eventually leads them back to her grandson Timo, who has a connection to Jeff's former manager, Desecrate. Mickey is assigned to work the case of Lester Graham, a gambler who owed $20,000 to an on-line gambling company who is rumored to be very violent in their collection methods. Mickey is upset when Bailey asks her to San Francisco then takes his wife instead, but shrugs it off to Nicco.

When a trusted defence attorney crosses Mickey, she vows to exact her revenge, can the squad solve this one?

Tony and Ali investigate Theresa Sandiman, a prostitute Tony has long thought responsible for a murder.

While Ali and Logozzo investigate the murder of retired teacher Merv Doucette, they are surprised to learn that, after a stroke, Doucette's behavior had changed drastically, and he'd gone from being a mild-mannered school teacher to a sex fiend who went to swinger parties. His wife, also a teacher, just happened to teach at Radford, where Jackie had gone to school. While Eddie tries to figure out how much money Jackie's family must have had to send her to Radford, which Logozzo estimates costs in the neighborhood of $30,000 a year, Jackie helps Ali question the widow after they realise that the prime suspect, Donnie Coombs, works for her, and came into a windfall the day after the insurance payout on Merv's life.

While I.A. investigates Ali for shooting at a man she thought was holding a gun (it was a remote control), Mickey and Nicco do stakeout duty together looking for Kirk Lennox and get on each other's nerves. Ali pairs up with Bill while reinvestigating the murder of Clara Pritchard, while Mickey comes under fire from Nicco, who wants her to lie and support Ali's original belief that the man was holding a gun. When Nicco learns that Mickey is sleeping with Bailey Gallanson, he berates her for refusing to lie for Ali yet being willing to sleep with Gallanson, who is not only married but has young children.

Ali investigates the death of Philip Morris, a teen who was believed to have committed suicide by jumping off the Capilano suspension bridge six years earlier. Coscarella worries his son Leo may be gay after Frank sees him embracing another guy after returning from a rave.

Still torn up over his separation from Wanda, Len relentlessly pursues a serial killer as Wanda seeks sole custody of their two daughters.