A 21-year-old man was stabbed multiple times on Wednesday at a movie theater during a screening of The Shallows, which stars Blake Lively.
The attack occurred in downtown Santa Rosa, a city in Northern California.
The suspect has been identified as Delonte Anthony Hart, 23, who has been homeless for about four months, according to reports.
The Santa Rosa Police Department described the incident on their Facebook page.
"The suspect, who was unknown to the victim, approached him from behind and stabbed him several times in an unprovoked attack," the post read.
"Witnesses tended to the victim's wounds until police officers and emergency medical personnel arrived."
Audience members who saw the stabbing provided a description to police and pointed out the direction he went following the attack.
Officers were able to locate the suspect within minutes and placed him under arrest for attempted murder.
The victim, whose name was not released, was transported to the hospital and treated for multiple life-threatening stab wounds and is "expected to survive."
A motive for the attack is unclear, but police described it as "random and frightening."
Lively has not yet commented.
Last July, another violent movie theater attack occurred in Lafayette, Louisiana during a showing of Amy Schumer's Trainwreck.
A gunman entered the theater and opened fire in the crowded cinema, killing two and injuring nine before taking his own life.
In response, a distraught Schumer told Vanity Fair that after hearing the news, she wished she'd never wrote the film.
"I was by myself in a hotel, and I was just like, I wish I never wrote that movie," she said.
Since then, Schumer has been a staunch advocate for tightening gun laws and has campaigned on the topic with her cousin, New York State Senator Chuck Schumer.