Back in 2014 Dustin Diamond, best known for playing "Screech" on Saved by the Bell, was arrested in a Wisconsin bar for stabbing a guy. He's since been convicted and, as of Friday, has started his four-month sentence at a Wisconsin prison. 

Although he claims he was defending his girlfriend, Diamond was charged with two misdemeanors—one for carrying a concealed weapon and the other for disorderly conduct. However, he was found not guilty of recklessly endangering public safety, which would have been a felony charge.

“I sincerely apologize to everyone involved,” Diamond stated during his sentencing last 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.”

Anyway, four months should go by pretty quickly.