"Big Brother" alums Memphis Garrett and Christmas Abbott were involved in a wild fight outside their Florida bar with a couple of upset patrons ... and the vicious beatdown was caught on video.
The whole thing went down in January outside their Ft. Lauderdale spot, No Man's Land. As for what sparked the violence ... one source tells us the couple walked inside and asked for drinks, but Memphis told them they were closed, and when they refused to leave things got heated.
However, a different source -- who was inside the bar -- tells us the couple wasn't in the establishment, and the fighting all started and ended outside.
Memphis and Christmas' attorney, Brian Karpf, says Memphis was attacked by the guy.
Karpf says Christmas -- who was awaiting surgery for a neck injury -- tried to pull Memphis away but got hit by the other woman. You see a bartender trying to break things up.
Christmas says she called the cops and filed a report because the couple continued to throw things at the windows and wouldn't leave. According to her attorney, she opted to not press charges but got assurance the couple would not return.
Fans of "Big Brother" remember the 2 first met during season 22 of "Big Brother: All-Stars" when they jumped into an alliance together early on. They confirmed they were an item after the season ended, and tied the knot last year.