NBC's Thursday night comedy block returned ... and not many viewers tuned in.

"Saturday Night Live Weekend Update Thursday" opened the night at 8 p.m. to 5.2 million viewers and a 1.6 rating in the 18-49 demographic. According to NBC, "Up All Night" brought in 3.1 million viewers and a 1.3 rating.

The final season of "The Office" debuted to 4.3 million viewers, down from its Season 8 premiere which had 7.6 million viewers, but in line with its Season 8 finale, which scored 4.5 million viewers. In the 18-49 demo, "The Office" was strongest with a 2.1 rating. "The Office" ended Season 8 with 4.5 million viewers.

"Parks and Recreation" kicked off Season 5 with 3.5 million viewers and a 1.7 rating, beating its Season 4 finale (3.4 million) in viewers. Both the finale and Season 5 premiere had a 1.7 rating. Still, that's a decline from the Season 4 premiere, which debuted to 4.1 million viewers.

"Rock Center" had 4.1 million viewers and a 1.1 rating at 10 p.m.

On Fox, "The X Factor" had 9.9 million viewers and a 3.4 rating while "Glee" had 7.4 million with a 2.9 rating.

CBS aired reruns, all of which topped the NBC lineup in terms of total viewers. On ABC, "Wipeout" wrapped its season with 4.35 million viewers and a 1.4 rating. "Grey's Anatomy" and "Scandal" were in reruns.

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  • 30 Rock

  • Betty White's Off Their Rockers

  • The Biggest Loser

  • Community

  • Fashion Star

  • Law & Order: SVU

  • Grimm

  • Parks And Recreation

  • Parenthood

  • Smash

  • The Office

  • The Voice

  • Up All Night

  • Whitney

  • 1600 Penn

    Benjamin Stockham as Xander, Martha MacIsaac as Becca (seated), Bill Pullman as President Dale Gilchrist (seated), Amara Miller as Marigold, Josh Gad as Skip, Jenna Elfman as Emily Gilchrist (seated), Andre Holland as Marshall Malloy

  • 1600 Penn

    Amara Miller as Marigold; Jenna Elfman as First Lady Emily Gilchrist; Bill Pullman as President Dale Gilchrist; Martha MacIsaac as Becca; Josh Gad as Skip; Benjamin Stockham as Xander

  • Go On

    Allison Miller as Carrie, Khary Payton as Don, Suzy Nakamura as Yolanda, Matthew Perry as Ryan, Laura Benanti as Lauren, Julie White as Anne

  • Go On

    Matthew Perry as Ryan King

  • Revolution

    Tracy Spiridakos as Charlie, Anna Lise Phillips as Maggie , Zak Orth as Aaron

  • Revolution

    JD Pardo as Nate, Tracy Spiridakos as Charlie, Zak Orth as Aaron, Anna Lise Phillips as Maggie

  • Revolution

    Billy Burke as Miles

  • Revolution

    Anna Lise Phillips as Maggie, Graham Rogers as Danny, Tim Guiee as Ben, David Lyons as Bass Monroe, Billy Burke as Miles, Tracy Spiridakos as Charlie, Andrea Roth as Rachel, Maria Howell as Grace, JD Pardo as Nate, Zak Orth as Aaron, Giancarlo Esposito as Lt. Neville

  • The New Normal

    Ellen Barkin as Jane, Andrew Rannells as Bryan, Georgia King as Goldie, Bebe Wood as Shania, Justin Bartha as David

  • The New Normal

    Bebe Wood as Shania; Andrew Rannells as Bryan; Justin Bartha as David; Georgia King as Goldie

  • The New Normal

    Andrew Rannells as Bryan, Ellen Barkin as Jane, Nene Leakes as Rocky

  • Save Me

    Anne Heche as Beth

  • Save Me

    Anne Heche as Beth Waring

  • Save Me

    Heather Burns as Jenna, Alexandra Breckenridge as Carly, Michael Landes as Tom Waring, Anne Heche as Beth Waring, Madison Davenport as Emily Waring, Lamman Rucker as John

  • Chicago Fire

    Teri Reeves as Hallie, David Eigenberg as Christopher Hermann, Charlie Barnett as Peter Mills, Lauren German as Leslie Shay, Monica Raymund as Gabriella Dawson, Taylor Kinney as Kelly Severide, Jesse Spencer as Matthew Casey, Eamonn Walker as Battalion Chief Walter Boden and Merle Dandridge as Kay Fitori

  • Do No Harm

    Steven Pasquale as Dr. Jeffery Kohl/Ian Price

  • Do No Harm

    Steven Pasquale as Dr. Jeffery Kohl/Ian Price

  • Do No Harm

    Steven Pasquale as Dr. Jeffery Kohl/Ian Price

  • Deception

    Meagan Good as Joanna Locasto

  • Deception

    Meagan Good as Joanna Locasto

  • Deception

    Meagan Good as Joanna Locasto, Victor Garber as Robert Bowers

  • Deception

    Victor Garber as Robert Bowers, Meagan Good as Joanna Locasto, Katherine LaNasa as Sofia Bowers, Tate Donovan as Edward Bowers, Laz Alonso as Will Moreno

  • Next Caller

    Jeffrey Tambor as Jefferson Mingus

  • Guys With Kids

    Anthony Anderson as Gary, Tempestt Bledsoe as Marny

  • Guys With Kids

    Anthony Anderson as Gary, Jesse Bradford as Chris, Zach Cregger as Nick

  • Guys With Kids

    Jamie Lynn Sigler as Emily, Zach Cregger as Nick, Tempestt Bledsoe as Marny, Anthony Anderson as Gary, Sara Rue as Sheila, Jesse Bradford as Chris

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