Speaking to The Sunday Times magazine recently, the actress revealed that she collapsed on stage four days from the end of the show's run following a traumatic year.
WATCH: Suranne Jones reveals behind-the-scenes look at Gentlemen Jack series two
The star had lost her mum just over a year earlier and had given birth to her first child at around the same time. "I'd lost my mum and had a child and was just trying to work through it all," she said.
Explaining that her collapse was perhaps something to do with "fight or flight", she said: "I was trying to fight something, tell a story and be a character, when my body was saying, 'You can't be on this stage right now because you're experiencing something else much more pertinent and you need to rest because you've had trauma.'"
After her West End show concluded, Suranne went straight into filming for Gentleman Jack series one, after which she suffered a breakdown. "It wasn't until after I'd finished filming the first series that I suddenly went, 'Oh my God,' because I hadn't dealt with what had happened to me with Frozen," she said.
Suranne stars in the BBC's Gentleman Jack
The Doctor Foster star then returned to therapy and started taking medication, which she continued until the pandemic hit in 2020.
"The medication is a choice and it's not for everybody," she said. "If you've had quite a few knocks, like I had in a row … I needed that help."
After her father sadly passed from coronavirus in January 2019, Suranne and her husband, Laurence Akers, were quick to act and she went back on the medication, knowing she "needed help".
Suranne married her husband Laurence in 2015
"I think anyone that has had a rock bottom in that way, particularly with their mental health, you hopefully go into a care system where you have therapy and doctors around you, guiding you so that you can recognise the signs," she explained. "So I still have ups and downs, but I definitely know how to ride them now."
Gentleman Jack continues on Sundays at 9pm on BBC One.
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