By Samantha Highfill
April 25, 2021 at 10:01 PM EDT

Warning: This post contains spoilers about episode 3 of The Nevers.

Amalia True loves a good fight, and the same can be said for her real-life counterpart, Laura Donnelly. Speaking to Amalia's epic underwater battle in Sunday's episode of The Nevers, Donnelly says, "It is one of my favorite weeks of filming ever."

The major action sequence, which saw Amalia take on a very large man with the ability to walk on water, involved working in a water tank, a first for Donnelly. "We were at the underwater tank in Pinewood, which is where they've done all the underwater Bond stuff," says Donnelly. "It has so much history so I was thrilled to be there, but once I got five meters underwater and they asked me to take off my goggles and my breather I suddenly got terrified. I don't get scared very easily, especially not with physical stuff — I've always felt really confident in that arena — and so that was really the first time that I've ever been in a situation where I thought, 'I am figuratively and literally out of my depth here.'"

The Nevers
Credit: Keith Bernstein/HBO

In the end, all it took for Donnelly to overcome her fear was to channel Amalia. "As soon as I put on Amalia's costume, suddenly I was not remotely bothered," she says. "I was only just excited to be there because suddenly I had a completely different mindset, I was Amalia in the water. I had a week of that and it was so much fun. It's one of the best parts about being an actor is that you get to learn these new skills and you get to go into situations that you otherwise never would've been put into. I felt like I came away having really achieved something and had a load of fun at the same time."

Donnelly's co-star Ann Skelly, who plays Penance, chimes in, saying, "I would like to add to that, even though I was not there, Laura Donnelly spent a week underwater. Who can say that? She is amphibious. I still can't get over it. I can't breathe when I watch that scene and it troubles me what you're doing when we're not in scenes together. That's why I think Penance is a great influence because she keeps you afloat."

The Nevers airs Sundays at 9 p.m. ET on HBO.

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