To the average TV viewer, it may sometimes look like movie stars and TV stars seemingly waltz into any studio set they choose, smile big, give a few fist bumps and score some extra air time.
The audience always seems to enjoy the surprise cameo, as do the performers, who often are fans themselves.
And of course, Mr. or Ms. Superstar are certain to love the attention and fun of being on a show once in a while without having to commit to the grind or the contractual obligations of being a regular cast member.
Here are 15 of our favorites.
17) Richard Belzer, X-Files, The Wire, Arrested Development
Richard Belzer’s character, John Munch, has the longest run of any character in all of American TV. He’s been portraying the character since 1993 on the hit crime show Homicide: Life on the Street.
After its cancellation the character spun off into Law and Order: Special Victims Unit, and from there it’s been a long and fascinating journey into one of TV’s most underrated staples.
It would probably be easier to list all of the shows Belzer hasn’t appeared on as Munch. The character pokes his head into shows like The X-Files, Arrested Developmen, and The Wire, sometimes in a serious dramatic performance and other times for a quick gag. It’s always fascinating to watch Belzer work his magic.
Munch has been on TV for 22 seasons of television, longer than both Kelsey Grammar’s Frasier Crane and Marshall Matt Dillon from Gunsmoke. He’s appeared in semi-canonical roles on a staggering nine series across five different networks, with dozens more cameo roles in others.
He’s even appeared in puppet form on The Muppets and as Belzer himself shooting an SVU scene on 30 Rock. Sadly, the character has recently been retired from SVU, meaning the long and successful career of Munch has finally come to a satisfying close.