Dustin Diamond, who made his name by playing Screech in Saved by the Bell, checked into a Wisconsin jail on Friday to begin serving a four-month sentence. The actor was arrested in December 2014 in connection to a Christmas Day barroom fight during which he stabbed a man with a switchblade. Diamond was charged this June with two misdemeanors: carrying a concealed weapon and disorderly conduct. He was not found guilty of the more serious felony charge of recklessly endangering public safety. At the time, Diamond argued that he drew the blade in self defense, hoping that it would deescalate the situation in the bar and protect his girlfriend, Amanda Schutz, who was found guilty of disorderly conduct. Diamond later dropped his appeal in December. “I sincerely apologize to everyone involved,†the actor said during sentencing in June. “This was the single most terrifying experience of my life … This is all I’ve been able to think about for the last six months.â€