Viola Davis, Kristen Wiig, Jon Hamm and More Added to Star-Studded "Stand Up to Cancer" Lineup

Celebrities including Viola Davis, Kristen Wiig, Jon Hamm and Zach Galifianakis will appear on the Stand Up to Cancer fundraising telecast on Friday, Sept. 9, the organization announced Thursday.

Matt Bomer, Dave Franco, Sonequa Martin-Green, Rob Riggle, Tony Hale, Terry Crews, Mel B and Bree Turner were also added to the lineup, which will air on more than 60 networks and streaming channels in the U.S. and Canada.

They join previously announced stars Ben Affleck, Matthew McConaughey, Emma Stone, Anna Kendrick, Josh Gad, Niecy Nash, Eric Stonestreet, Alison Sweeney, Ken Jeong, Marcia Cross, Greg Grunberg, Danielle Campbell, Charlie Wilson, Brittany Daniel and Stand Up to Cancer co-founder Katie Couric, with musical performances by Celine Dion and Dierks Bentley, Keith Urban and Little Big Town.

Stand Up to Cancer is a charitable organization that raises funds to accelerate the pace of cancer research and treatment. The Sept. 9 show will be the organization's fifth biennial fundraising telecast.

The hourlong, commercial-free special will air Friday, Sept. 9 at 8/7c on ABC, CBS, FOX and NBC, along with several cable networks including Bravo, Comedy Central, E!, Fusion, FXM, HBO, LMN, Logo, MLB Network, National Geographic, Pivot, Showtime, STARZ, TBS, VH1 and WGN America.