Who killed Liar's villainous Andrew Earlham? At long last, we have the answer

If you're still sorting things out in your brain after that action-packed, time-travelling finale, here's what happened...

What was Andrew's original getaway plan?

To backtrack: initially, when he realised the police were onto him, Andrew Earlham fled to the harbour and hid in his pal's boat. His plan was to vanish without trace, and he summoned old 'friend' Oliver from Edinburgh to help him put that into action by collecting his belongings, cash and car keys from the hospital.

However, when Andrew heard that his teenage son Luke Earlham (Jamie Flatters) had tried to kill himself and was seriously ill in hospital, he couldn't resist going to see him; and after that, he couldn't resist breaking into Laura's house and stealing her necklace before returning to the boat.

Unfortunately for Andrew, during this outing he and Oliver were spotted by boatyard worker Carl Peterson (Howard Charles), whose wife Winnie Peterson (Amy Nuttall) was one of Andrew's victims – and Carl was determined to get his revenge. He tied Andrew up, took him out to sea and pushed him overboard. But while Carl was convinced he'd just killed Andrew (and later committed arson to destroy the boathouse and boat and cover his tracks), Andrew somehow made an unlikely escape and swam back to shore where he stormed over to the boathouse.

There, he confronted Laura, blaming her for his son's suicide attempt. "You stole my life," he said, ominously. "Now I'm going to steal yours."

How did Andrew plan to frame Laura?

It was time for a new plan! Andrew had clearly been scheming for a while, and now he thought he'd come up with a genius idea. Not only would he disappear, but he'd stage his own murder – so the police would never come looking for him. And even better, he'd frame Laura for killing him.

After a brief interlude sleeping rough, Andrew found a shipping container and made it his new HQ. Using a stolen phone, he then summoned Oliver back from Edinburgh to help him once again. Primary school headteacher Oliver was reluctant, but Andrew had some excellent blackmail material: footage of Oliver drugging and sexually assaulting a young man, which he'd previously agreed to delete after Oliver initiated him into the world of being a serial rapist. But all these years later, Andrew claimed to still have that incriminating evidence, and so Oliver was bound to help him.

Oliver was dispatched to the hospital to pick up the car keys he'd dropped the first time around, which had since been helpfully handed into lost property by Laura's sister, Nurse Katy Sutcliffe (Zoë Tapper). Andrew also extracted vials of his own blood and splashed them around the shipping container so it looked like the scene of his own death. Artfully, he placed Laura's necklace at the 'crime scene'.

Next, he planned to take Laura's car keys while she was kayaking, drug her, and drive her car to the shipping container. He'd do a runner and Oliver would tip off the police; the police would find the 'crime scene' and the car, and Laura would end up in jail.

But things went wrong – because Laura hadn't brought her car with her after all. Oliver was sent on foot to her house to collect it with keys stolen from Laura's bag, but meanwhile Laura herself returned from kayaking and headed back into the boathouse.

Andrew looked on, panicking. He'd spiked her water bottle, but now the timings were out! Oliver hadn't returned with the car yet! Climbing out of the car, he peered into the boathouse and saw Laura already collapsed on the floor.

Who killed Andrew?

But – twist! – Laura wasn't unconscious. She'd clocked that her keys were missing and someone had messed with her stuff. When Andrew approached, Laura surprised him with a knife.

Unfortunately, she immediately lost the upper hand. Andrew and Laura were now locked in a life-or-death struggle, as Andrew abandoned his 'frame Laura' plan in favour of a new 'kill Laura' plan. She fled to the marshes, and he chased; they grappled in the mist, fighting to grab hold of the knife – and finally Laura slashed him across the throat and killed her tormentor.

At this point, Laura apparently decided not to call the police, even though she'd probably have had a solid defence. After the events of series one, she'd come to distrust the police and the justice system, so she just went home and waited for Andrew's body to be found by passing kayakers later that day.

How did Oliver frame Laura?

In Andrew's absence, Oliver opted to continue the plan of framing Laura for Andrew's murder – presumably in order to keep himself out of the picture, now that the original threat of blackmail had passed. (We're not sure if he 100% knew that Laura was, in fact, actually responsible for Andrew's death; but he did know that Andrew was dead.)

As planned, Oliver planted Andrew's car keys in Laura's bedroom. He also blackmailed DS Rory Maxwell (Danny Webb) with information obtained by Andrew before his death; he had evidence that Rory's policeman son Greg Maxwell (Jack Colgrave Hirst) had been admitted to hospital three times for cocaine overdoses, a revelation which would destroy Greg's career if it went public.

Choosing to save his son, Rory took the satnav out of Laura's car at the police pound and gave it to Oliver to reprogram. When it was returned to the car, it now magically had Andrew's shipping container saved as its last destination.

How did Laura prove that Oliver was framing her?

Lots of people actually brought Oliver down together!

Laura's sister Katy and her estranged husband Liam Sutcliffe (Richie Campbell) realised that the keys Katy had picked off the locker room floor were probably Andrew's, and they managed to find the CCTV footage of Oliver (name as yet unknown) collecting them. They then worked out where he was staying in town, and Laura and Katy bribed the inn's receptionist – who told them that this man had been visited by a teenager called Luke. Carl also confirmed it was the man he'd seen walking with Andrew.

Laura and Katy paid Luke a visit, and he denied actually meeting Oliver when he went to the inn. However, from Andrew's belongings, Laura did glean Oliver's real name. DI Karen Renton (Katherine Kelly) also approached Luke, and now she learned some valuable information: this Oliver guy had been deeply, deeply worried about the police finding a mysterious video recording hidden somewhere in the Earlham house. Also, Luke had found Oliver's story extremely suspect, had searched the house, and had found that horrific footage of Oliver.

Meanwhile, Laura had some new information from DI Vanessa Harmon (Shelley Conn) about who'd accessed her car, and she now began to suspect DS Rory Maxwell. After clashing with him, she stole his phone and found out everything about Greg and the blackmail and put several pieces together.

Thankfully, Rory and Greg did the right thing and 'fessed up. So in a risky manoeuvre, Laura broke her bail conditions and went to Edinburgh with her sister to confront Oliver in person and get him well and truly rattled; Oliver then picked up the phone and called Greg, the police recorded it all, and Oliver was promptly taken into custody.

How did Laura get away with it?

All signs now pointed to Oliver, and he was charged with the murder of Andrew Earlham (as well as blackmailing a police officer and sexual assault). But DI Karen Renton still had her gut feeling that Laura was the real killer... and as we now know, she was right.

But despite her crusade against Laura throughout series two, DI Renton now decided to let things stand. She had no evidence against Laura, and she also had experienced a big change in perspective.

When we first met DI Renton, we discovered that she'd seriously contemplated killing her abusive ex; but that this man was now behind bars. She felt that justice had been served, and she was confident in her decision not to take the law into her own hands. But as Laura's case came to an end, DI Renton was informed that her ex had been released from jail and had just beaten his girlfriend so badly that she ended up dead.

Would it have been better to murder her abuser after all – and save victims down the line? Had the justice system let everyone down? And if Laura had saved future victims by killing Andrew, why should she be punished?

What happens next?

It's a happy ending, of sorts, as we say goodbye to these characters for the final time.

Laura is back with her boyfriend, Ian Davies (Kieran Bew), and they've agreed that Laura doesn't have to tell him what really happened. Liam and Katy are back together, too. Rory is probably going to jail, but he's reconciled with DI Vanessa Harmon and has faced up to what he did. Vanessa and her wife have healed their rift and are excited to welcome their first baby. And it looks like poor Luke is heading somewhere else to start a new life.

Meanwhile, even though he didn't kill Andrew Earlham, Oliver is where he belongs: behind bars. And Laura walks free.

• Where was ITV thriller Liar filmed?
• Liar series 2 full cast: actors and who they play in ITV's thriller

Check out what else is on with our TV Guide