Discovery Channel's "The Devils Ride" -- a reality show about a San Diego biker gang -- has some real deal bad dudes... because TMZ has learned, one of the stars just got arrested for stabbing a guy while burglarizing his house.
According to docs, Sandman -- real name Robert Johnston -- was arrested on December 27 for burglary, attempted murder (with a knife), assault with a deadly weapon and making criminal threats.
In charging documents, prosecutors say Sandman broke into the victim's house on Dec. 22 with the intent to commit burglary, and at some point, stabbed the victim ... inflicting "great bodily injury."
Sandman is still behind bars, being held on $755,000 bail.
By the way, "Devils Ride" isn't currently airing, but rumor is it's coming back for a 2nd season.
Reps for Discovery had no comment.