Arnold Morton Muntz, played by Ryan Thomas Brown, is a recurring character seen on Beverly Hills, 90210, the first series of the Beverly Hills, 90210 continuity, appearing first in the fourth season and recurring until the end of the series.
Muntz was a friend of Steve Sanders, who he originally met as part of the KEG fraternity. Largely used as comic relief, Muntz was usually seen languishing in the background at parties getting drunk or dispensing boos himself. He was largely loyal to Steve and was one of the first brothers to blackball John Sears when the vote came to banish one or the other from their fraternity.
He was virgin until Steve lent him Andrea Zuckerman's dorm room to use with his girlfriend, Sherry.
As the series went on, he usually showed up at special events, such as birthday parties, graduations, and weddings, eventually getting married himself to Julie Muntz. Muntz was in attendance to David and Donna's wedding in the series finale.