“I Had No Idea About Ryan’s Twist” — ‘Mare of Easttown’ Actor Cameron Mann Opens Up About the Shocking Finale

When HBO’s Mare of Easttown first aired, audiences expected a gritty small-town crime story anchored by Kate Winslet’s raw, unflinching performance. What they didn’t expect was one of television’s most gut-wrenching twists — and neither did actor Cameron Mann, the young performer behind the show’s most devastating reveal.

In the explosive finale of the limited series, Winslet’s detective Mare Sheehan finally uncovered the heartbreaking truth behind the murder of teenage mother Erin McMenamin (played by Cailee Spaeny). For weeks, the case had torn apart the fictional Pennsylvania town of Easttown — a place already weighed down by addiction, loss, and secrets. But the revelation that Erin’s killer was Ryan Ross (Cameron Mann), the 13-year-old son of Mare’s best friend Lori (Julianne Nicholson) and her husband John (Joe Tippett), sent shockwaves through viewers and critics alike.

A Twist That No One Saw Coming

Cameron Mann, who portrayed Ryan, revealed in a post-finale interview that he had no idea about his character’s role in the murder when he first joined the project.

“When I got the part, I thought Ryan was just this quiet, sensitive kid who loved his mom and had a complicated family,” Mann told EWHBO. “I had no clue he would end up being such a huge part of the story — or that I’d be playing the person who caused all of this.”

The show’s creative team kept the shocking twist tightly guarded. Even cast members received only partial scripts to prevent leaks. Mann says he didn’t find out the truth until production was already underway.

“It was a total surprise,” he said. “And much like Ryan, I also had to keep it secret for a very long time.”

The Moment That Broke Everyone

In the finale, viewers were first led to believe that John Ross — Ryan’s father — was the killer. John had been having an affair with Erin, his teenage cousin, and had fathered her child. When he confessed to the crime, it appeared to close the case. But Mare, plagued by doubts and her own instincts, continued to dig.

Her relentless pursuit led to a devastating discovery: Ryan had found out about his father’s affair and had confronted Erin, terrified the relationship would destroy his family. In an emotional confrontation gone wrong, Ryan pointed his father’s gun at Erin, threatening her to stay away. The gun discharged by accident — killing her instantly.

“That’s what makes it so tragic,” Mann explained. “Ryan thought he was protecting his family. He was just a kid who didn’t understand the consequences.”

When Mare finally arrests the boy, it’s one of the most powerful moments of the series — Winslet’s performance a masterclass in heartbreak and restraint. Lori, torn between her love for her son and her moral responsibility, pleads with Mare not to take him. The scene is almost unbearable in its realism.

“It’s not a villain story,” Mann said. “It’s about love, guilt, and the lies we tell ourselves to survive.”

Behind the Curtain

According to series creator Brad Ingelsby, the decision to make Ryan the killer was planned from the start. The goal, he explained, was to reflect the painful consequences of secrets within families, rather than craft a traditional whodunit ending.

“We didn’t want the finale to be about shock value,” Ingelsby told EW. “We wanted it to be about emotional truth — about how tragedy can ripple through generations.”

For Mann, filming those final scenes was an emotional challenge. “There was a day when we shot the scene of Ryan being taken away,” he recalled. “It was quiet on set. Nobody talked between takes. Kate [Winslet] hugged me afterward and said, ‘You did something very brave today.’ I’ll never forget that.”

Winslet’s Guiding Hand

Kate Winslet, who also served as executive producer, was reportedly protective of the young actor throughout filming. Crew members described her as a mentor figure, ensuring Mann felt supported during the heavy material.

“Kate was incredible,” Mann said. “She helped me understand that even though Ryan did something terrible, he’s still a child. She kept reminding me to play the emotion, not the guilt.”

Winslet later praised Mann’s performance during a press interview, calling him “a revelation” and noting how his quiet innocence made the twist all the more devastating.

The Ending That Stayed With Everyone

The finale, titled Sacrament, didn’t end with Ryan’s arrest but with Mare’s emotional reconciliation with Lori — a friendship fractured by betrayal and grief. In the final shot, Mare climbs into the attic where her own son died by suicide, finally facing her own trauma. It was a haunting, hopeful close to a story about brokenness and healing.

Since airing, Mare of Easttown has earned critical acclaim for its performances, writing, and emotional honesty. Winslet won multiple awards for her role, and Mann’s portrayal of Ryan has been hailed as one of the most memorable child performances in recent TV history.

“It’s strange,” Mann reflected. “I didn’t know the twist when I joined, but now it feels like I’ve lived with it forever. Ryan’s story — it’s tragic, but it’s also human.”