The 37-year-old, who is one of the original stars of the BBC period drama, confessed that the plastic sheets used during filming were a hindrance and slightly affected their acting abilities.
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Speaking at the BFI and Radio Times Television Festival on Sunday, Helen said: "It's so nice now restrictions have lifted. We can actually get close, hug and do proper acting. It's two years into our relationship and we're like, 'Nice to meet you, how do we do this?' It's so awkward."
Creator Heidi Thomas also teased big things for Trixie, adding: "Something interesting and rather wonderful will happen for Trixie this series. She has big news coming up."
In the latest series, viewers were excited to see Helen's character Nurse Trixie and widower Matthew (played by Olly) share a kiss after growing close in series ten.
Helen with her on-screen love interest Olly Rix
Although the scene was shot in a romantic setting, the protocols set in place during the pandemic overshadowed the sweet moment – something Helen has described as "the most unsexy thing you could ever do".
"We became masters at kissing through Perspex," she said via Radio Times in January. "It's probably the most unsexy thing you could ever do. A man comes along with a little spray and a window wipe and wipes away your spit after every take. Horrific."
The star, who filmed the 11th series whilst she was expecting her second child with partner Jack Ashton, added: "There were a few [takes]. It takes a while to get there. It was so mechanical, we'd turn our head to the left or bring your cheek in a bit or your head. Awful. Awful. So embarrassing."
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