Six Four ending explained: Was Julie Mackie's disappearance case solved?

But as well as that, Chris is confronted with the unsolved past case of Julie Mackie, a local girl who had disappeared and whose father, Jim, we meet in the first tense episode of the series. He seems to know exactly what the term "Six Four" refers to and throughout the series, we come to understand that what seems like a missing person's case is actually a tale of corruption, politics, power and deceit.

But what happens to Chris and Michelle's daughter? And does the case of Julie Mackie get solved in the end? Read on for everything you need to know about the series finale of Six Four.

Six Four ending explained: was Julie Mackie's disappearance case solved?

Essentially, yes – but not in the neatly tied up way you may think. Instead, we find out that Julie is dead and has been since her disappearance was first reported to the police because, well, she didn't just disappear one day. She walked into a burglary happening in her family's home, fell and died.

The person who was in their home was Steven Bryce, the same man that confessed to Gary's murder and was tasked with retrieving documents from Jim's home.

We learn the truth in the finale, when both Jim and Gordon are telling the story separately. At this point, Jim and Gordon have kidnapped Robert Wallace's 17-year-old daughter, Annabel, to force him to confess the truth after both being personally motivated by the deaths of their loved ones. But what is the truth?

Well, the police set up a meeting point for the kidnapper and Robert to meet in the hopes of returning Annabel to safety, but the police have their suspicions that it could be Jim Mackie, the father of missing girl Julie Mackie. They say that Robert and Jim were close in the past – the minister agrees and says that Jim was his mentor – and ask Robert about Annabel's rumoured statements that her father has information about the fact that Julie is dead.

But Robert quashes any concerns, saying it's a political issue relevant to Jim being part of the Scottish National Party.

In the background of the episode is Bill Martin and his heavies, who are tailing Chris and newly arrived Michelle who, now knowing that their daughter Olivia is alive and well, decide to solve Julie's case and save Annabel. Bill is tracking Chris's car but also breaks into Gordon's rural police station, getting closer to the house that Gordon and Jim are holding Annabel in.

We then start to find out the truth as Jim sets off to meet Robert and Gordon is left alone with Annabel. He admits that he was the person pretending to be her teacher, messaging her to meet him in the forest and that’s when he kidnapped her. He explains that he was one of the police officers on the case when Julie went missing and says that he wants the person who upended people’s lives to pay.

He talks about getting revenge on Robert, but also says that Gary would’ve wanted the same thing. Gary McLean was the officer who Gordon was in a closeted relationship with, and the same officer who was murdered after being part of the team to investigate Julie's disappearance.

Locating the house, Chris and Michelle take alternative routes round the front and back but when Chris comes into the house, Gordon pulls a gun on him stating that he doesn't see himself as a police officer anymore. But Chris says he knows what happened to Jim’s daughter. Steven killed her, the same man who Gordon thought killed Gary but Chris says he didn't. Steven told him that he didn’t kill Gary and that the police forced him to confess to Gary’s murder or they would reveal that he was the one to kill Julie.

Steven was paid to break into Jim’s house to steal a document from a safe but Julie wasn't meant to be there. He panicked, she fell and hit her head. The people Steven was working for needed time to get rid of Julie’s body so they made him call the house to make it look like a kidnap had taken place. Gordon says that Gary kept a recording of the call and gave copies to him and Robert, thinking that Robert was someone who could "make a change", but he was wrong.

Gordon tells Chris that the documents Steven was sent to get were files and emails outlining just who Robert is and his plans to stop Scottish independence. He gives over the USB of information to Chris, leaving him with the decision to expose the truth or not and Chris and Michelle leave with Annabel, as Bill and his men come to confront Gordon.

What happens to Jim Mackie?

Elsewhere, at the same time, we see Jim and Robert at the organised meeting point – but on the way, Robert tells Philip to remember their pact of helping each other out, no matter what. When they meet, an emotional Jim asks Robert why he didn’t tell him that Julie was dead. “You were my friend,” he says.

Jim then confronts Robert with the truth, telling him that he wants Robert to go public with the recording that Gary sent him. He says that it's evidence that proves that Robert is a murderer, but it's also the recording of the man Robert paid to break into Jim’s house but now claims never happened.

Jim says that Robert had Gary murdered because he was asking questions about the documents, the same documents that showed there were multiple MI5 attempts to infiltrate their political party and stop Scottish independence. The agent was tasked with splitting the SNP and his codename was Six Four, who Jim thinks is Robert.

But as their face-off grows more tense, Robert starts to gaslight and confuse Jim, saying he was the one to kill Julie and that he is the politician pushing for independence. He recalls the evening Julie went missing, reminding Jim of the argument the father and daughter had about a dress they'd bought for her and she refused to wear.

Jim has the same dress in his bag and brings it to the meeting point, but as he bends down to retrieve it, he waves the hanger at Robert and a sniper shoots Jim dead. Soon after, we see Bill asking Gordon whether he thought he’d get away with this and that it won’t bring Gary back, but Gordon says: “I know, I just want to see him again” and shoots himself.

What happens to justice minister Robert Wallace?

In the finale's final moments, we see that Robert is appointed deputy first minister and that his reunion with his daughter was far from pleasant. But who cares, because he's triumphed in his political career and could very well be a major step closer to his true undercover mission, right? If what Jim and Gordon say is the truth, Robert is Six Four and could completely upend Scotland if he continues to power through the ranks.

We do know that his last words to Jim were that he was sorry, so if we ever needed more reason to believe that the politician isn't exactly who he says he is, it was that slight admission of guilt.

What happened to Chris and Michelle?

After the debacle in the Scottish highlands, we see them glammed up and ready to go to Philip's family party, but there Bill says to Michelle that he hopes Chris isn’t bitter and that they "did good". "Chris isn’t the only one that knows, remember that," Michelle says.

Bill tells her that they paid Annabel’s teacher debts off and Bill tells Michelle that he would hope Chris doesn’t do anything “to wreck his brother’s career”, pointing at some kind of veiled threat. Inside the house, Chris plugs in the USB and plays the recording for Philip, which incriminates him as the one that picked up the phone for that fateful call.

Philip confesses that he knows what he did and lives with it everyday but says there aren’t any consequences for people like Robert. It turns out that Robert confronted Philip after he got the recording from Gary, starting their beneficial working relationship. Philip urges Chris to keep his mouth shut, saying that they’d come for him and his family if he doesn’t, but Chris leaves the USB with Philip saying that he’s either one of us (the police) or one of them.

We see Chris and Michelle leave the party hand in hand, looking much happier than we have seen them before. Although their daughter Olivia isn’t missing, her room remains untouched and they both sit there on her bed. We of course now know that Olivia found out that Chris is not her biological father and a criminal named Pierce is, but the married pair seem to be working hard to get back to where they were.

The episode finishes with Chris admitting that Olivia said she’d only come back if they could sort themselves out and Michelle says: "Let’s do that then."

Six Four starts streaming on Thursday 30th March on ITVX. Check out more of our Drama coverage or visit our TV Guide and Streaming Guide to see what's on tonight

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