Dept. Q star reacts to end of Merritt Lingard's dramatic and traumatic storyline

In the first episode, we find out that Merritt went missing four years ago, and has been held captive in a hyperbaric chamber for all of that time.

The scenes set in the chamber are naturally tense and claustrophobic, and speaking exclusively with RadioTimes.com, Pirrie revealed how she got herself into the mindset of someone held captive in that state for so long.

She said: "It's a big thing. I did a lot of research about the pressure chambers and stuff like that. I also did a lot of research about solitary confinement and just reading accounts of it, which were obviously quite affecting."

She continued: "There's a few websites that are dedicated to voices of people who are in captivity currently or have experienced it in various different ways, whether they're in prison or whether they're being held in some other way.

"So I read a lot of accounts of what starts to happen to both your mind and body and the two in tandem, and how one affects the other.

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"And that was all really rich, because then the specificity of what type of pain you're in and whether your sense of reality and what types of things start to happen and become unbearable.

"What becomes unbearable is sometimes not the obvious things. So that was fascinating and quite awful to read in many ways."

Pirrie also spoke about the end of the season, which sees Merritt being saved at the last minute by Matthew Goode's Carl Morck and Alexej Manvelov's Akram Salim.

When asked what she hopes for Merritt going forward after she's saved, Pirrie said: "She should go on a nice holiday. I think she should go on a nice all-inclusive, just have a nice... a few massages or two.

"But I don't know, I have a feeling that she wouldn't... What do you do when you're spat out of something like this? I hope that she can kind of lead a slightly more peaceful life, but I also hope that she can kind of rebuild herself."

Dept. Q season 1 is available to stream now on Netflix. Sign up for Netflix from £5.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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