"Under the Christmas Lights" taken from No Doubt singer's new holiday album
Adam Levine, James Valentine performed 2014 hit "Sugar," Queen's "Crazy Little Thing Called Love" in 'Tonight Show' web video
Superstar makes last-minute 'Tonight Show' appearance to show support for Fallon after his mother's death
'Voice' coach also delivered backwards-lyric version of her 2004 hit "Since U Been Gone"
Smashing Pumpkins singer releases new solo LP, 'Ogilala'
Father-daughter duo paid tribute to late rock icon with twangy 'Tonight Show' performance
Singer also joined cast of 'Riverdale' for 'Family Feud'-styled game, "Search Party"
Singer recruited men to hold teddybears, lick lollipops during live version of electro-pop single
Rappers utilized live drummer, black-and-white visuals for playful live spot
Comedian, singer also mimed Harry Styles, Niall Horan, Luis Fonsi in 'Tonight Show' sketch
Single appears on Gotti's collaborative mixtape with Mike Will Made-It, 'Gotti Made-It'
Band also performed atmospheric 'Joshua Tree' track "Bullet the Blue Sky," criticized President Trump's decision to rescind DACA
'Tonight Show' host battled actress Sarah Paulson in "Wheel of Impressions," which also featured imitations of Drew Barrymore, Al Pacino
'Rainbow' singer teams with 'Tonight Show' band for acoustic spin on Animals' classic
'Rainbow' singer also joined Fallon, Anthony Anderson, NPR's Terry Gross for late-night version of 'Password'