Now, the 34-year-old Canadian nomad is serving a 57-year prison sentence for murder in New Jersey, and his story is the center of a newly-released Netflix documentary: The Hatchet Wielding Hitchhiker.
Kai, whose real name is Caleb McGillvary, went viral in a 2013 news clip detailing how he saved a woman from her attacker, hitting him thrice over the head with his hatchet.
Kai's heroic act and laid-back attitude made the vigilante an overnight star. News stations around the world were eager to speak with the courageous surfer dude, who appeared on Jimmy Kimmel Live! a little more than a week after going viral.
His 15 minutes of fame might have translated into a media career, but Kai wasn't interested in stardom. He was happy living as a nomad — surfing and smoking weed.
Three months after Kai went viral, he was arrested for killing 73-year-old Joseph Galfy, a lawyer from Clark, NJ, who was found dead in his home wearing nothing but his socks and underwear.
While Kai claimed he'd been sexually assaulted by Galfy, detectives in the Netflix documentary say there were no signs of a struggle at the crime scene: Galfy had been brutally beaten to death, possibly in his sleep.
Kai was identified as a suspect but was on the lam for several days. It wasn't until he was spotted by a coffee shop worker in Philadelphia, who called police, that Kai was arrested.
He sat in a New Jersey jail cell for five years before his trial began on April 1, 2019.
Online well-wishers who'd seen Kai's 2013 video had set up a legal fund for his defense, but it only prolonged the inevitable: The hatchet-wielding hitchhiker was sentenced to 57 years in prison for Galfy's murder.
Click here to follow Daily Voice Newark and receive free news updates.