Elizabeth Olsen loves a puzzle

Elizabeth Olsen didn’t know it was a true story.

Reading an early script for “Love & Death,” the new HBO Max miniseries premiering Thursday about a small-town Texas housewife accused of ax-murdering a friend in 1980, Olsen believed Candy Montgomery’s crime to be a work of fiction. She thought the Texas Monthly articles she received with the script were short stories. It could easily have been imagined, the unsettling narrative of a woman who strikes up an affair with the husband in a fellow churchgoing couple and who, after confronted by the wife, ends up on trial for her brutal killing.

When meeting with writer David E. Kelley and director Lesli Linka Glatter, executive producers on the series, Olsen learned the truth. “It’s not O.J.,” the 34-year-old actress says, referring to the high-profile murder trial of former football player O.J. Simpson. But it still happened, and real lives were affected. She wondered how the team would present this astonishing story to audiences without sensationalizing it. And how much creative license would she be afforded in the role?

Quite a bit, it turned out. Though Montgomery was written about in the press — and in the book “Evidence of Love: A True Story of Passion and Death in the Suburbs,” from which “Love & Death” also draws — there was little footage of her to go off. (Last year’s Hulu miniseries “Candy,” starring Jessica Biel as Montgomery, hadn’t yet been released.) Olsen created her own version of Candy to ground the series, which over seven episodes explores how someone so ambitious and well-liked by her community could also behave selfishly and contain a lurking darkness.

The balance is difficult to master, but Olsen has walked such tightropes before — recently for her Emmy-nominated performance as a tortured witch in Marvel Studios’ “WandaVision,” but also dating back to her debut feature role as a disoriented cult survivor in 2011’s “Martha Marcy May Marlene.” All mixed up in disturbing crimes, these characters don’t always endear themselves to viewers. The actress, however, savors the challenge of deciphering perplexing behavior.

“I don’t know what people want out of something they’re watching, besides the baseline of being entertained,” Olsen says. “But I do think we want to watch people fail and see how they resolve whatever the failure is. I think we want to watch people make decisions we think we’d never make because it’s like trying to watch someone work themselves out of a puzzle.”

Glatter thought to cast Olsen because of her performance in “Martha,” which the director says left her “gobsmacked.” Olsen was unknown at the time outside of being a younger sister to child stars Mary-Kate and Ashley, who in the past had looped her into their on-screen antics, including a 1994 music video in which they implored a forlorn-looking little Lizzie to “B-U-T-T out” of their business. In a way, she did; Olsen opted out of acting as a child and trained as a young adult at New York University’s Tisch School of the Arts.

While Olsen always wanted to act — the desire is “so embedded in every memory I have,” she says — insecurities got the best of her early on. It wasn’t just the potential comparisons to her sisters, but growing up around so many aspiring actors in Los Angeles that convinced her that she needed to first figure out, as she recalls, “Who am I? And how am I different? And how am I unique?”

She wanted to earn her spot in the industry, and NYU — along with the affiliated Atlantic Theater Company and the Moscow Art Theatre School, where she spent a semester — helped her get there.