Lukas Gage's memoir "I Wrote This For Attention," out Oct. 14.

Lukas Gage is rewriting the rules of the celebrity memoir.

Ever since his cheeky breakout turn in Season 1 of HBO’s “The White Lotus,” the winsome heartthrob has become a familiar face in TV shows such as “You,” “The Other Two” and “Overcompensating,” with scene-stealing big-screen turns in “Smile 2” and “Companion.”

But in his revealing new “I Wrote This For Attention," Gage eschews the dishy blind items and A-list name drops that we’ve come to expect from most Hollywood tell-alls. Instead, the San Diego native writes thoughtfully and maturely about his upbringing: the collective impact of his father’s abandonment, his brother’s heroin addiction, and his mother’s penchant for gambling.

He also gets candid about his struggles with substance abuse and coming to terms with his sexuality, as well as his diagnosis with borderline personality disorder. He says the latter was responsible in part for his whirlwind six-month marriage to Chris Appleton, a celebrity hairstylist for clients including Kim Kardashian.

“A few months after my wedding in ape suits, something clicked,” Gage writes. “I had an elusive moment of clarity where I didn’t recognize myself anymore. … I understood that while I could blame a lot of my behavior on my diagnosis, there was also a lot I had to confront. That there had been so much from my growing up that maybe stopped me from growing up.”

Lukas Gage reveals childhood sexual abuse in new memoir 'I Wrote This For Attention'

In the book’s most harrowing chapter, Gage, 30, writes candidly about being abused by a counselor at an acting camp when he was 11 years old. Gage writes he was kissing a girl when a counselor climbed into their tent, instructing them to disrobe while he watched them.

The “Gossip Girl” star recalls feeling “detached” and “scared,” shaking with anxiety in that moment.

“I knew it was wrong as it was happening,” Gage writes. “It was wrong of him. It was wrong that I was a little turned on, that I felt uncomfortable, that I felt nothing at all. It was wrong that I loved the thrill of doing something forbidden. My skin felt dirty, and my stomach tensed with fear. But I knew one thing for sure: I was good at putting on a show.”

After it was finished, Gage said there was an “unspoken agreement” among the three of them that they would never talk about it.

“Nothing out of the ordinary, I tried telling myself,” Gage writes. “This stuff happens all the time, especially at camp. This is just what hooking up feels like. There’s always someone with more power. One person’s always a little uncomfortable.”

It wasn’t until the actor was in his 20s and in therapy that he fully grasped that what had happened to him was wrong.

“I was so disconnected from myself,” he remembers. “I’d spent so much of my life wanting to know the secrets of the adult world. Now I knew way too many of them.”

The 'White Lotus' actor looks back on 'Mad Men' firing, working with Sydney Sweeney

It's not until the end of the book that Gage recounts his early days trying to make it as an actor. In one chapter, he recalls his agent getting angry that he was let go from AMC’s “Mad Men.” He was cast as a love interest for Kiernan Shipka’s Sally Draper, until the wardrobe department discovered that he had a massive tattoo along his ribs, “as well as a Mockingjay perched on my calf. (Yes, from ‘The Hunger Games.’ I really connected to the books when they came out!).”

After he was fired, he was told that it would have taken too much time to cover his tattoos with makeup for the character’s shirtless scene.

“According to Kiernan Shipka, who, as fate would have it, became of my closest friends, I was referred to as the ‘tattoo boy’ on set,” Gage writes. “My legacy lived on for the rest of the season.”

After a recurring role in Season 1 of “Euphoria,” Gage booked “The White Lotus,” which shot in Hawaii. “It felt like being at a summer camp, but the actors were actually talented and no one was getting molested,” Gage writes.

He remembers how his “White Lotus” castmates, including Molly Shannon and Jennifer Coolidge, encouraged him to share his now-viral 2020 audition video, in which a casting director criticized his “tiny” apartment, unaware that Gage could hear him. He also credits Sydney Sweeney for being his anchor during filming.

Sweeney "was the one person there I knew from back home, and though she was another of my ‘Euphoria’ costars whose star had been rising faster than mine, it was clear she hadn’t grown jaded or any less in awe of the opportunity before us,” Gage writes. “Sydney’s groundedness had always buoyed her, and on the shoot, it kept me afloat as well.”

If you are a survivor of sexual assault, you can call the National Sexual Assault Hotline at 800.656.HOPE (4673) or visit hotline.rainn.org/online and receive confidential support.

This article originally appeared on USA TODAY: Lukas Gage opens up about sexual abuse in memoir 'I Wrote This For Attention'

Reporting by Patrick Ryan, USA TODAY / USA TODAY

USA TODAY Network via Reuters Connect