He performed on 'Sing Along With Mitch' and was a teenage idol in Japan before spending 46 years on the iconic kids TV program.
Thompson and Mitchell portray older versions of their hit 1996 sitcom characters who encounter an armed robber, while host Palmer comedically plays up her newly announced baby bump.
The 'SNL' veterans opened up about working with new castmembers Marcello Hernandez, Molly Kearney, Michael Longfellow and Devon Walker.
Here's a complete list of which mystery musician unmasked themselves to reveal the winner at the end of each season of Fox's The Masked Singer.
SZA was also previously announced as a performer for the popular sketch comedy series' December episodes.
Sunday's telecast will have something for everybody -- a defining characteristic of the show that Dick Clark created in 1973.
The 'Full House' star also addressed her original statement, blaming "the media" for "seeking to divide us."
GLAAD also issued a statement, saying it was "irresponsible and hurtful" for the 'Full House' actress to "use tradition as a guise for exclusion."
The No Doubt singer is already brainstorming what to get her husband when he departs the singing competition.
The Boss will play four songs from his forthcoming 'Only the Strong Survive' album.
