U2's Bono reached out to Carrie Underwood and the country superstar didn't let him down.

Underwood will perform in U2's surprise World AIDS Day (RED) event in Times Square tonight by personal invitation from U2 frontman Bono, according to a press release. The World AIDS Day event begins at 7:30 p.m. and Kanye West will also be performing. 

U2's Adam Clayton, The Edge and Larry Mullen Jr. will be joined by Bruce Springsteen and Coldplay's Chris Martin, who are also donating their time. The stars are stepping in for Bono as he recovers from injuries sustained in a November bike accident.

"This year is a World AIDS Day like no other," Bono said, speaking from Dublin. "The world reached a tipping point in the fight against AIDS when more people were newly added to life-saving treatment than were newly infected with the virus. A lot of people are calling it the beginning of the end of AIDS."

"We wouldn't be at this point without American leadership, people from the left and the right," Bono continued. "Today, 13 million people have access to life-saving treatment, up from 300,000 just over ten years ago. Americans don't know the role they have played in this fight. Tonight's event is to inform them and thank them."

"A (RED) Thank you Presented by BANK OF AMERICA)" will broadcast live on YouTube and radios across the U.S. including iHeart Radio, which is becoming iHeart (RED) for World AIDS Day and as part of ESPN's Monday Night Countdown.  

World AIDS Day takes place at Duffy Square in Times Square on Broadway, between 46th & 47th Streets, and the entrance is at 50th and Broadway.