Michelle Monaghan talks Maggie's 'True Detective' [SPOILER]

LOS ANGELES, Feb. 24 (UPI) -- In this week's True Detective, Michelle Monaghan's Maggie Hart really went for it.

(Warning: Spoilers for the HBO drama's sixth episode, "Haunted Houses" follow.)

From the moment True Detective introduce us to Maggie, viewers suspected she was on a collision course with Rust Cohle (Matthew McConaughey).

Ahead of Sunday's episode, Marty (Woody Harrelson) had successfully convinced Maggie to give him another chance at repairing their marriage after his affair with Lisa (Alexandra Daddario) comes to light. But by 2002, Marty is cheating again, and Maggie's had enough. After striking out trying to hook up with a stranger, she turns to Rust, and we finally find out what broke up both Marty and Maggie's marriage and Marty and Rust's professional partnership.

"I think her decision to sleep with Rust was the ultimate betrayal and revenge for Maggie after what Marty’s done to her," Monaghan said. "It was the only way that she could save herself and save her family. She had to devastate him in such a way that he would leave them alone forever.

True Detective, following the model of American Horror Story, has been billed as a limited series in which a second season will feature new stars and a new story. Monaghan said the events of "Haunted Houses" was a big reason why she joined the show.

"We just went for it," she said, of filming the scene with McConaughey. "I mean, we filmed it over the course of a few hours, different parts of it."

"But what you saw, it was a 'wham, bam, thank you ma’am' deal," she said. "It didn’t take us long to figure it out. We just looked at each other and said, 'Let’s just do this.' So we did. The first time, I turned around and kept going and it felt really raw and the energy was explosive. So we stuck with playing it all out right there in that span of time."

The show has been showered with accolades, but has fielded some criticism that all its secondary characters, aside from Rust and Marty, have been two-dimensional. But Monaghan said she found Maggie's interaction with the two men in her life as an important driver of the story.

"I thought she was fully fleshed out, I thought she had a very interesting and complicated relationship with two men and it unraveled in a very devastating and intimate way, and a really honest way," she said. "I felt very connected to it. I never really questioned that going into it."

True Detective has just two episodes left in its first season.

[Vulture]