HBO’s crime drama “True Detective” has now become famous for its intense action scenes, with the bloody shootout involving Rachel McAdams’ SWAT officer Ani Bezzerides in Sunday’s episode being no exception.

While the episode certainly got the adrenaline flowing in fans, it was especially grueling to film for McAdams.

“That one took about five days,” the actress told Variety while promoting her drama “Southpaw.” “That was pretty intense. I actually puked during that scene. When I was running and reloading my gun — it actually wound up being about 200 yards, it was like two football fields — and I was just going all out and we did it a couple of times.”

Although it was physically challenging, McAdams said she embraced the action-packed scene.

“It was my own fault,” she said. “I had been drinking that EmergenC and going hard to just try to keep my energy up. Not a good combination, the running and that. But I kind of felt bada–. Like yeah, let’s do it again. It was really fun though. I like action. I like being thrust into that.”

McAdams said that, since she’s not on Twitter, she is “a little in the dark” about fans’ reactions to the scene — and says that’s probably a good thing.

She also joked that this was one of the instances where getting in shape for the part didn’t pay off.

“I was running in my spare time to be in shape for it. A lot of good it did me,” she said.