Greg Sestero

Greg Sestero is an American actor, filmmaker, model, and author. He is best known for his portrayal of Mark in the 2003 cult film The Room, as well as for writing the memoir The Disaster Artist, which details his experiences during the making of the movie and was later adapted into an award-winning 2017 feature film.

Sestero was born on July 15, 1978, in Walnut Creek, California, to an American father of Italian and Irish descent and a French mother of French and Italian heritage. He grew up in Danville, California, where he attended Monte Vista High School. At age 12, Sestero wrote a sequel screenplay for Home Alone and submitted it to Hughes Entertainment, receiving an encouraging letter from filmmaker John Hughes that inspired him to pursue acting professionally. During his junior year of high school, Sestero began modeling in Milan and Paris for designers including Giorgio Armani and Gianfranco Ferré. He subsequently returned to the United States to study at the American Conservatory Theater in San Francisco and eventually moved to Los Angeles after signing with Hollywood agent Iris Burton.

Sestero began his screen acting career with minor roles in television shows such as Nash Bridges and films including Gattaca and Patch Adams. In 1999, he landed a lead role in the horror movie Retro Puppet Master and appeared on the soap opera Days of Our Lives. Having met Tommy Wiseau in an acting class in 1998, Sestero was cast as Mark in Wiseau's self-financed 2003 film The Room. Despite critical failure and a poor initial box office performance, the movie developed a public cult following through late-night interactive screenings around the United States and internationally. Sestero attended many screening events and later appeared in a remake of The Room released in October 2025.

In October 2013, Sestero published his memoir, The Disaster Artist, through Simon & Schuster. The book won Best Non-Fiction at the 2014 National Arts & Entertainment Journalism Awards, was nominated for an Audie Award for Best Humor Audiobook, and reached the New York Times Bestseller List. In 2017, the book was adapted into a major feature film directed by James Franco, who starred as Wiseau alongside Dave Franco as Sestero.

Throughout his career, Sestero has modeled for major brands such as Tommy Hilfiger, Armani, and Ralph Lauren. His subsequent projects include appearances in the television series Fashion House, Miranda Lambert's award-winning "White Liar" music video, short comedy projects, and the feature film Dude Bro Party Massacre III. He wrote and co-starred in the 2018 film Best F(r)iends alongside Wiseau. Sestero later guest-starred in Netflix's The Haunting of Bly Manor, starred in the horror comedy Cyst, and made his directorial debut with the 2021 film Miracle Valley. He lives in Southern California.