Nathan Lane (Modern Family (2009)); Kristen Schaal (The Last Man on Earth (2015)). Also: Børns perform. ...

Kelsey Grammer (Killing Jesus (2015)); Paula Pell; The Count. ...

Jeremy Piven (Mr Selfridge (2013) and Entourage (2015)); David Benioff and Daniel Weiss. Also: Marina Lambrini Diamandis (aka Marina and the Diamonds) perform. ...

Ben Stiller (Workaholics (2011)); Elisha Cuthbert (One Big Happy (2015)); journalist Chris Hayes. ...

Jesse Tyler Ferguson (Modern Family (2009)); Christina Hendricks (Mad Men (2007)). Also: Charles Hamilton and Rita Ora perform. ...

Jay Leno; Sara Foster and Erin Foster (Barely Famous (2015)); comedian Seaton Smith (Mulaney (2014)). ...

Lena Dunham (Girls (2012)); sportscaster Erin Andrews (Dancing with the Stars (2005)). Also: Tove Styrke performs. ...

Shailene Woodley (Insurgent (2015)); Jason Biggs (The Heidi Chronicles); filmmaker Alex Gibney (Steve Jobs: The Man in the Machine (2015)). ...

Keri Russell (The Americans (2013)); Sen. Ted Cruz. Also: Smallpools perform. ...

Jada Pinkett Smith (Gotham (2014)); Ginnifer Goodwin (Once Upon a Time (2011)); Robert Smigel. Also: Kate Pierson sits in with the 8G Band. ...

Kenneth Branagh (Wallander (2008)); Felicity Huffman (American Crime (2015)). Also: Purity Ring perform; Kate Pierson sits in with the 8G Band. ...

Tom Selleck (Blue Bloods (2010)); Anne Heche (Dig (2015)); author Marlon James. Also: Kate Pierson sits in with the 8G Band. ...

Kelly Ripa (Live with Kelly and Ryan (1988)); Lee Daniels (Empire (2015)). Also: Echosmith perform; Kate Pierson sits in with the 8G Band. ...

Christina Aguilera; Colin Quinn (Trainwreck (2015)); Kurt Braunohler (Bob's Burgers (2011)). ...

The cast of Parks and Recreation (2009). ...

Mary J. Blige; Stephen Amell (Arrow (2012)). Also: MisterWives perform. ...

Zachary Quinto (The Slap (2015)); Mae Whitman (The Duff (2015)); fashion designer Carolina Herrera. ...

Kathy Griffin (Fashion Police (2002)); Peter Sarsgaard (The Slap (2015)). Also: The Mavericks perform. ...

Matthew Perry (The Odd Couple (2015)); Taraji P. Henson (Empire (2015)); Anders Holm (Workaholics (2011)). ...

Kevin Costner (McFarland, USA (2015)); Portia de Rossi (Scandal (2012)); Westminster Dog Show announcer David Frei with some dogs. ...

William H. Macy (Blood Father (2016) and Shameless (2011)); basketball analyst Kenny Smith. Also: The Districts perform. ...

Sienna Miller (American Sniper (2014)); Tracee Ellis Ross (Black-ish (2014)); writer Brian Koppelman. ...

Bobby Moynihan (Sisters (2015)); Eugene Levy and Dan Levy (Schitt's Creek (2015)). Also: The Bots perform. ...

David Duchovny (Aquarius (2015)); models Candice Swanepoel and Lily Aldridge; Brooks Wheelan (Better Off Single (2016)). ...

Glenn Close (Anesthesia (2015)); Gabrielle Union (With This Ring (2015)). Also: J. Mascis. ...

Debra Messing (The Mysteries of Laura (2014)); comedian Horatio Sanz; chef Mario Batali. ...

John Oliver; Mike Greenberg and Mike Golic (Mike and Mike (2006)). Also: Kid Ink performs with Elle Varner. ...

Felicity Jones (The Theory of Everything (2014)); former NFL player Hines Ward; comic Sebastian Maniscalco. ...

Jennifer Lopez (The Boy Next Door (2015)); Nick Kroll (Kroll Show (2013)). Also: Lupe Fiasco performs. ...

Lauren Graham (Parenthood (2010)); Rainn Wilson (Backstrom (2015)); Brian Michael Bendis. ...

Don Cheadle (Avengers: Age of Ultron (2015)); Ruth Wilson (The Affair (2014)). Also: Night Terrors of 1927 perform. ...

Kristen Stewart (Still Alice (2014)); Andrew Rannells (Girls (2012)); comic Phoebe Robinson. ...