Coldplay to Headline Secret Police Ball Indie | Tuesday 31st January 2012 | Osh Coldplay is set to headline this year’s Secret Police Ball, in celebration of its 50th anniversary. This year’s ball, to be held in New York, will be the first to be held in the United States, and will also be the first to feature both music and comedy acts. The event will raise money for Amnesty International and will take place in March.