Kristen Wiig and Jack Whitehall are among the latest names announced to perform at The Secret Policeman's Ball - in New York.
The Bridesmaids star and the young British comedian will join Russell Brand and Coldplay for the concert held at Radio City Music Hall on March 4 in aid of Amnesty International.
US comedienne Sarah Silverman and The Mighty Boosh star Noel Fielding has also been added to the line-up along with Statler and Waldorf from The Muppets.
Other stars from both sides of the Atlantic who have joined the show to celebrate free speech and Amnesty International's 50th anniversary, include Mock The Week's Micky Flanagan, the US Office star Rashida Jones, as well as Andy Samberg, Peter Serafinowicz and Jason Sudeikis.
The British-based fundraising event was launched back in 1976 with celebrities like John Cleese. Over the years, Bono, Sting and others have participated.
The last Secret Policeman's Ball was in 2008 in London and this is the first time it's being held in New York City.
The show will be broadcast on Channel 4 in the UK.
Amnesty International's Kerry Moscogiuri said: "We're extremely excited by the great host of talent who have given up their time to take part in Amnesty's Secret Policeman's Ball.
"We expect this will be a great evening of entertainment that will also succeed in throwing a spotlight on the importance of Amnesty's work on defending all human rights, and in particular free speech."