Guilt ridden Officer Nick Barron returns to work following a deadly shooting; Ben Chartier's transfer to Station 19 from Québec's rural police force turns rocky after a split-second decision triggers an internal investigation.

A showdown between rival street gangs goes terribly wrong, leaving Ben’s life in danger. Squad 19 gathers at Marie’s for the Sergeant’s party and Isabelle discovers Nick may have feelings for someone else.

The first of the month brings “Welfare Day” to 19 – Nick and Ben handle an array of belligerent civilians; the day caps off with a cataclysmic domestic disturbance.

Tyler botches a takedown of a gang of rapists that nearly costs Nick his life, and leaves Ben to question Tyler's fitness on the job. Nick brings Harvey to Houle’s BBQ, which goes crudely awry.

Nick butts heads with J.M when they are assigned patrol together. Beatrice embarks on a new romance.

A cover-up comes back to haunt Nick and Ben, pitting them against Gendron. Nick’s frustrations mount when Ben encroaches on his personal life.

Squad 19 is pulled into a big raid. Nick and Ben clash over a politically explosive DUI while Isabelle and Nick find common ground when Theo starts to act out.

An amber alert ripples through 19. After realizing he’s been shutting Audrey out, Nick makes a strong commitment to her. Ben continues to date Amelie without telling Nick, adding another stress to their partnership.

The squad is devastated when one of their own is brutally assaulted and left clinging to life, causing personal vendettas to collide with protocol in the aftermath.

In the climactic season finale, Nick receives devastating news, and struggles to contain his explosive response. A surprise visitor lands in Ben's life, forcing him to make some very hard decisions.

The entire squad is embroiled in an intensely tragic school shooting with consequences that will profoundly impact all of their lives.

In the aftermath of the school shooting, the squad copes with the trauma as it affects them in ways they never expected.

After the arrest of a misunderstood homeless man and the retrieval of a runaway, Nick and Ben realize that not everyone can be saved.

The squad becomes involved in a feud with firemen; little mistakes cause consequences.

Amelie takes a chance on Ben, while Nick and Isabelle receive shocking news about Theo.

The hunt for the mole takes a dramatic shift when Nick is pulled off patrol.

Housing evictions pit the squad against a community; Nick takes matters into his own hands when the mole investigation hits a wall.

After an accidental death, violent protesters occupy an abandoned building and the squad must clear them out.

Ben and Nick are called in for questioning in the murder of a pedophile and the true identity of the mole is revealed.

With the mole on the run, the devastated squad turn on each other; Nick finally tells Ben the full truth about what he and Kaz have done.

The squad waits for findings in the Sgt. Houle case. Also, the squad is fractured, and multiple lives hang in the balance due to a horrific accident.

Nick probes his cousin's mysterious death, and before long a possible witness emerges.

Ben puts himself in hot water with Homicide when he tries to help Nick with his investigation into Kaz's murder.

Nick tries to walk the line when a wannabe mobster approaches him with a tempting proposition.

The city cuts public sector pensions, pitting the squad against their own.

Ben is drawn back home to Morin Heights when his father goes missing. Nick makes a deal with Martine.

Work-to-rule ends, with the squad returning to normal duty. Meanwhile, Nick hides secrets from Ben as he tracks his cousin's killer.

A misunderstanding results in tragedy, changing the lives of Nick and Ben forever.

Nick and Ben lean on each other in the aftermath of devastating tragedy, but Nick's lies threaten to drive them apart.

Nick and Ben discover the horrifying truth behind Amelie's death.

Nick and Ben decide to take down Elise to avenge the brutal murder of Nick's sister. Also, Nick is first on the site of a horrific event with numerous casualties, plus Ben and Audrey get swept up in a tragic accident.

With the investigation of Elise Roberge over, Ben volunteers for surveillance duty; Ben and Audrey face the consequences of their accident; the squad ends up in the middle of a growing gang war.

Ben's actions bring repercussions; in pursuit of justice, Ben and Nick encounter a person they thought they'd never see again; a new officer joins 19; the squad finds out something disturbing about one of their own.

The squad escapes to a cottage for the weekend, where alcohol and the intimate setting lead to conflict.

The patrollers of 19 struggle to find their footing. Nick realizes what he wants. Dulac loses control.

Ben faces consequences; Nick's new romance gets complicated; Dulac crosses a line; Audrey thinks about the future.

Ben's troubles become public; Nick faces a crisis; Dulac gets in over his head.

The squad works during a full moon; Suarez and Beatrice receive unexpected news; the squad works to prevent a tragedy.