Speaking to The Sunday Times Magazine, the actress revealed that her dad, Chris Jones, tested positive for coronavirus a week into filming for the new series and sadly died following three months in a hospital ICU.
WATCH: Have you caught up on series one yet?
The mum-of-one explained that while her and her brother, Gary, weren't able to visit their dad while he was ill in hospital, they were allowed to say their goodbyes shortly before his death in January 2021.
Following his passing, Suranne returned to filming but hadn't come to terms with the loss of her parent. She explained how the Covid restrictions served as a constant reminder of the virus that caused Chris' devastating death.
"You're filming in a pandemic, everyone is wearing masks. Every two days you've got someone coming in to test you. To have a parent pass of the thing that you are reminded of all the time… Your brain filters out stuff, so I couldn't remember my lines.
Suranne opened up about losing her father to coronavirus
"Most of the time I was going, 'What is it? What am I saying?' That will probably haunt all the crew. My brain was obviously going, 'This is not important.'"
The 43-year-old also revealed that she won't be tuning in to watch the latest series of the BBC drama, which returns to our screens in April. "I'm not ready to watch it because it's so full of memories mixed up with stuff," she said.
The second series of Gentleman Jack, which arrives this spring, will see Suranne reprise her role as Yorkshire landowner and 'the first modern lesbian', Anne Lister. She will be joined by Peaky Blinders actress Sophie Rundle, who plays her on-screen lover, Ann Walker.
Suranne stars opposite Sophie Rundle in the BBC drama
Gemma Whelan and Lydia Leonard will also be returning as Marian Lister and Mariana Lawton, while Gemma Jones and Timothy West will be back to play Aunt Anne and Jeremy Lister.
The new season also welcomes guest star Joanna Scanlan, who recently won a BAFTA for her performance in drama film After Love. She will be joining the cast to play Anne Lister's outrageous former lover Isabella 'Tib' Norcliffe.
Gentleman Jack season one is available to stream on BBC iPlayer and HBO Max.
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