When Detective Carl Morck (Matthew Goode) takes on management of a newly established cold-case unit in Scotland, he isn’t planning on solving any cases. The Department Q of the new show’s title is a PR opportunity for the embattled Edinburgh police department — and its unlikely leader, Morck, is a brash cop recovering in hectic fashion from a brutal shooting. 

For Constable Moira Jacobson (Kate Dickie), the job is essentially a babysitting gig — but fate has other plans for Carl Morck. “He goes down there and there’s a case from four years ago,” Goode tells Tudum. “Someone’s fallen off a ferry four years previously, and they never really got to figure out why or how it was caused.”

That someone is Merritt Lingard (Chloe Pirrie), a local solicitor whose story is intercut with the beginning of Morck’s investigation in the show’s first episode. Soon, Morck is diving deep into the mystery of Merritt’s disappearance, assembling a task force of misfits, and juggling his crumbling personal life. All in a day’s work for Department Q. 

Read on to uncover the truth about what happens to Merritt Lingard — and how Carl Morck builds a team capable of saving her. 

Why was Morck shot?

Dept. Q begins with a shocking cold open: Carl Morck and his partner, James Hardy (Jamie Sives), are shot while investigating a crime scene. Both survive, but a rookie cop is killed and Hardy is paralyzed. As Morck takes on the Lingard case, he continues to return to the events of that morning, struggling to cope with PTSD and survivor’s guilt. Regular therapy sessions with Dr. Rachel Irving (Kelly Macdonald) don’t help. 

The series never directly answers the question of who shot Morck and why (though a dream sequence does provide a few possibilities). But Morck manages to piece together a theory: The shooting was actually committed by two criminals who were working to distract from the real crime, the killing of the young police officer. By Morck’s logic, the killer had no reason to return to the scene and certainly not to flee while Morck and Hardy were still alive — unless it was all a ruse to cloak their real motive. The police were lured to the scene as a trap, acting on a report from a nonexistent daughter of the victim. When Morck passes this theory along, he finds at least some small portion of the peace he’s been seeking.  At the end of the series, Constable Jacobson assigns Hardy to run down the facts.

Jamie Simpson/Netflix

What happened to Merritt Lingard?

The story of Merritt Lingard’s disappearance is seemingly simple: On a ferry cruise with her disabled brother, William (Tom Bulpett), Lingard went missing. Did she fall overboard? Was she pushed? Lingard was spotted having an altercation with a belligerent William before she vanished; is he somehow involved?

Morck and his new assistant, Akram (Alexej Manvelov), investigate all of these possibilities and more. Akram is an IT expert assigned to Department Q to keep him out of Jacobson’s hair, but he’s also a Syrian expat with a mysterious past — one that makes him quite the asset to the newly formed department. He champions the Lingard case, arguing that something is definitely out of place; Lingard’s body never washed up on shore, and she was a high-powered solicitor who could have easily made enemies. 

Morck and co. soon uncover a few clues: first, a man wearing a mysterious hat with a bird emblazoned on it, drawn by the nonverbal William Lingard. Through conversations with the Lingards’ housekeeper, Claire (Shirley Henderson), and Merritt’s boss, Lord Advocate Stephen Burns (Mark Bonnar), the Department Q team becomes convinced that their missing person was kidnapped, not knocked overboard. 

They also find themselves falling down a few rabbit holes that turn out to be unrelated. Detective Constable Rose Dickson (Leah Byrne) misidentifies the bird William draws as a boobrie: the name of Merritt and William’s father Jamie’s boat. The bird is actually a cormorant. Oops.

The team also tracks down the connection between Stephen Burns and wealthy businessman Graham Finch (Douglas Russell). Before Lingard’s disappearance, she was head prosecutor on the case of Finch’s alleged murder of his wife — and Lingard failed to win a conviction. Morck and Akram uncover evidence that Burns pressured his subordinate not to call a witness who could have won her the case. 

Finch doesn’t take kindly to the team nosing around, and he sends men to intimidate Morck’s stepson, Jasper (Aaron McVeigh). But it’s a red herring; while Finch is certainly a murderer and Burns certainly corrupt, they had nothing to do with Lingard’s disappearance. The real answer is much more sordid.

Who is Sam Haig?

Morck and Dickson uncover a seemingly crucial clue in the hunt for Lingard — she was having a relationship with a now-deceased journalist, Sam Haig (Steven Miller), who approached her about corruption in her department. But the detectives quickly hit a snag, struggling to pin down Haig’s movements in the days before his climbing death. When they realize that Haig was having a separate affair at the same time as his tryst with Lingard, they conclude that he couldn’t have been in two places at once. The Haig Lingard was seeing was a fraud. 

This ties back to an earlier mystery: how Merritt’s brother, William, became disabled. In flashbacks, we see young Merritt’s relationship with Harry Jennings (Fraser Saunders), the local teen who would later be accused of beating William into a nonverbal state during a robbery gone wrong. But in the final episodes of Dept. Q, we learn that Harry’s antisocial brother Lyle was actually the one who beat William — and that Merritt helped plan Harry and Lyle’s aborted robbery turned assault in an attempt to steal her own mother’s jewelry and fund an escape from her dull island home. Harry died trying to escape from the police — a death that Lyle and his mother blamed on Merritt.

As Department Q soon discovers, everything about the case revolves around Sam Haig’s relationship with Lyle Jennings. The pair knew each other as children at an institution for troubled boys, and Jennings latched onto Haig, even calling him by his brother’s name. The pair reconnected as adults — and Jennings killed Haig and tossed him off of his local climbing spot. After assuming his identity, Jennings started a relationship with Lingard and, ultimately, kidnapped her. In a twisted choice that recalls Lyle’s father’s own abuse, Lingard has been trapped and tortured in a hyperbaric chamber for the past four years. She’s trapped on the grounds of the Jennings’ shipping company, Shorebird Ocean Systems (whose logo is, you guessed it, a cormorant).

Justin Downing/Netflix

How does Department Q save Merritt Lingard?

After tracking down the address of Lyle’s mother, Morck and Akram run into a problem: how to depressurize the chamber without killing Lingard. As a recovering Hardy coaches them through the controls over the phone, the pair are surprised by Jennings. Bringing the series full circle, Morck takes a bullet in the shoulder for Akram, who then dispatches Jennings with the help of his own mysterious combat training. Mrs. Jennings flees the scene and shoots herself after being confronted by a police cordon, and Lingard is safely removed from the chamber.

Merritt and William are reunited, and she begins the process of piecing her life back together. She never meets Morck; the pair pass each other like ships in the night at police headquarters. Morck has other plans. He leverages his newfound knowledge of Burns’ corruption to convince the lord advocate to increase the Department Q budget, fast-track Akram’s promotion to full detective, and, of course, get Morck a nicer car. 

The final scene of the show is simple: Morck, back to work in the dripping Department Q basement, smiling softly as Hardy returns to work on crutches — a happy ending, as far as these things go. Case closed. 

Dept. Q is now streaming on Netflix.