New pictures from this evening’s penultimate episode of Liar hint at a dark new danger for Laura (Joanne Forggatt) as we reach the climax of ITV’s dark drama series.

Laura’s attempts to build a case against Andrew for raping her hit several stumbling blocks last week as a previous victim of his sex attacks in Scotland refused to tell their story.

[Read more: Liar viewers shocked as show takes darker twist]

[5 surprising facts about Liar star Ioan Gruffudd] 

Liar episode 5

And despite another attack from Andrew on detective Nessa Harmon (Shelley Conn), the despicable surgeon remains a long way off being caught.

The pictures released by ITV from episode five (October 9th) hint at a new threat for Laura, who is pictured in dark scenes, looking terrified and on the run.

Liar episode 5

Will there be another showdown with Andrew? And what twists lay in store for the show’s final two episodes?

Liar episode 5

Liar episode 5

[Read more: How many episodes of Liar are there?]

[Read more: Meet the cast of ITV's Liar]

Has it already got a second series?

According to The Sun, ITV has already signed up writers Harry and Jack Williams for a second series and are keen to extend it further in the style of Broadchurch.

The vision is already there for this to continue beyond series one. The hope was always that this show could become a major drama for ITV, and that looks to be happening. The wheels are already in motion for it to come back," said a source.

However, viewers shouldn't worry that this means they won't get answers in series one. Joanne Froggatt has confirmed that the first series will have definitive answers.

A second series is expected to focus on different characters.

[Where is Liar filmed?]

The majority of the series is shot in Deal on the Kent coast, but a number of locations were used to bring the tow to life.

Jack Williams revealed director James Strong's vision: "He had a specific look in mind and a specific vision of a place he wanted it to be,” writer Jack Williams explained at a screening in London.

“It has to feel specific, but not so specific that it doesn’t feel like it could happen in the world today. It has to feel like a very present thing that can happen anywhere and to anyone."

The marshes that you see in the credit sequences are in Tollesbury on the Essex coast.

And you can visit the lovely looking restaurant at the centre of the story, which is called Jasin's Restaurant. In real life, it's just a cafe which serves soups and sandwiches, rather than the swanky destination for Laura and Andrew's first date.

The pier scenes were filmed in Deal.

[Read more: Joanne Froggatt had reservations about rape drama Liar]

Who is in the cast?

Downton Abbey star Joanne Froggatt plays Laura Nielson, a smart and outspoken teacher who is in the middle of a break-up as the programme begins. She arranges to go out on a date with the father of one of her pupils, which leads to the disagreement that the drama hinges on.

Froggatt said of her character: “At the beginning of the series when we meet Laura, she’s a modern, intelligent woman, living in a nice place, with a great career. She’s someone who really knows her own mind.

“Then through events in the story, her life changes forever. She absolutely spirals into a realm she’s never experienced before, which is out of control and not something that’s part of her nature. We do find out later in the series that, like the other characters, she has secrets, and that she has the capability to lie about things, too.”

Ioan Gruffudd stars opposite Froggatt as Andrew Earlham, a recently-widowed surgeon who has a spotless reputation both at work and in the place that they live.

The Fantastic Four actor describes his character as “a good father, a surgeon, and pillar of the community. He is a character everybody loves and admires. He’s a great dad, confident and full of himself in a very charming, and disarming way”.

Other key characters in the series include Laura’s sister Katy Sutcliffe (Zoe Tapper), her husband Liam Sutcliffe (Ritchie Campbell), Laura’s ex Tom Bailey (Warren Brown), and DI Vanessa Harmon (Shelley Conn).

[Read more: Joanne Froggatt's best screen roles - From Downton to Filth]

What is the series about?

The nature of the thriller means that the cast can’t reveal too many spoilers, but the basic premise is that Laura and Andrew go on a date and we last see them having a great time – until it abruptly cuts to a very different atmosphere the next morning.

Laura has been set up for the date by her sister Katy, a nurse in the hospital where Andrew works as a surgeon. However, she also teaches his teenage son.

We don’t yet know how DI Harmon comes into the storyline, but Laura’s ex Tom is a police officer so he could have a bigger role in the drama than just their break-up scenes.

Katy is also said to be harbouring an explosive secret that could send shockwaves through her marriage – in fact writers Harry and Jack Williams have said that all their characters are lying in some way.

Jack said: “People are complicated and good characters are complicated. And the lies we tell ourselves are sometimes the most interesting of all.”

[Read more: Downton Abbey star Joanne Froggatt to star in new TV thriller Liar]

He added: “At the heart of it, it’s a show about deceit, about truth, and what people perceive to be the truth. That’s one of the things that interests us the most - that there are many different sides of any truth, and the most corrosive thing of all is when two people have diametrically opposed opinions on something.”

Why should you tune in?

Liar sounds like compelling viewing, but if you still need convincing, Hollywood star Gruffudd sells it well.

“I’ve got to be honest, the reason I’m back home in the UK, and back on British television for the first time in a decade, is Harry and Jack’s script,” he said.

[Read more: Ioan Gruffudd - 5 surprising facts about the Liar star]

“When I picked up the script I couldn’t believe what I was reading, it was one of the best scripts I have read in a long, long time. There have only been three times in my career where I’ve read something and have thought, ‘I have to play this part’, and this was one of them.”

Froggatt added that there was much about her character that she found difficult, which made her all the more interesting to play.

She said: “In terms of an actress approaching the role, she is possibly one of the most challenging characters I’ve played, and I’ve played quite a few.

“For many reasons it was quite emotionally and physically challenging. Quite often Laura makes decisions that I wished she wouldn’t. She makes some wrong turns certainly, and as an actress, I had to do a lot of research to find reasoning for the way she behaves, and the way she reacts.”

In fact, writer Harry said that they aimed to make the show uncomfortable viewing.

“We hope viewers feel conflicted, because they’re presented with characters who they will hopefully warm to before events unfold and challenge that,” he said.

“As you’re going forward, you’re forced to challenge your preconceptions of how much you like this person, whether you believe them or not.”

Episode five preview:

"Laura’s resolve to bring Andrew to justice deepens and she enlists Tom’s help in her plan. However, when a deception in Laura’s personal life comes to light, she is left with no one to turn to, and she resorts to dangerous methods to force Andrew’s confession. But she is not alone in her mission."

Liar airs Mondays at 9pm on ITV.

Catch up on BT TV via the ITV Hub app.

[Read more: Liar - Who do you believe? Episode 1 review]