Lily Gladstone flows over her Under the bridge Co-star Riley Keough.

Speaking to ET's Cassie DiLaura at the Los Angeles premiere of their new show on Monday, the 37-year-old Oscar nominee said she knew she wanted to join the project as soon as she heard who was attached to it.

“When I heard Riley was attached, I really wanted to work with her, so it gave me a lot of confidence too,” she said. “There was a little bit of hesitation about doing real crime so soon after Murderers of the Flower Moon, but I knew that if Riley not only starred in it, but played it on the EP, it would be a very compassionate deep dive into a story.

The show is based on Rebecca Godfrey's novel about the true story of 14-year-old Reena Virk (Vritika Gupta) who was brutally murdered after going to a party with friends and never returned home. The series follows the investigation through the eyes of Godfrey, but also through the eyes of Gladstone's police officer, Cam Bentland.

In Martin Scorsese'S Killers of the Flower Moon – a film that earned Gladstone her first Oscar nomination and made her a household name – she played Mollie Burkhart, a real-life member of the Osage Nation who was central to solving the Osage murders of the 1920s. That film was an adaptation of the 2017 nonfiction book written by David Grann that detailed the murders, including the murder of Burkhart's mother and sisters.

For Gladstone, the hesitation to move so quickly from one crime adaptation to another was offset by Keough, 34, putting together the scripts, which she says tell the tragic story in a nuanced and respectful way.

Gladstone said: “I feel like true crime is being commodified, it's being made so sensationalized and we forget the truth element of it instead of focusing on the crime. And the series has such a compassionate approach in the way we show Reena see – she is with In every episode you fall in love with her, you really sympathize with her family.”

While the show clearly tackles some dark and heavy topics throughout its eight-episode run, the actress told ET that she, Keough and their co-stars and crew members were able to have a lot of fun while off camera to bring humor and lightheartedness to the project.

“I feel like a lot of actors: when we are immersed in stories that are so heavy, there is a lightness that you bring to the work in between [scenes] because that's what keeps you going through it,” says the Fancy dance said star. “It's so easy to become curt and grumpy with people when something is bothering you, and that just affects the work. I think you give the work some credit by recognizing that it's a privilege to to be able to share these stories — we share other people's stories and there is a responsibility in that.”

As for the rumors that Gladstone and Keough would see an Emmy nomination for the show so soon after their respective nominations at the Oscars and Emmy Awards – Keough received a nomination for Outstanding Lead Actress in a Limited Series for Prime Video's Daisy Jones and the Six — the actress said she's not worried about what awards might come her way.

“This story gives you so many people, gives you so many characters and these kids are just incredible,” she said. “I remember saying to Riley, no matter what our storyline ends up being, the kids will carry the show and it will be a compelling, amazing story that is truly unique.”

Watch the series trailer in the player below:

Under the bridge will premiere on Hulu with the first two episodes on April 17, with subsequent episodes releasing weekly thereafter.