Pop-rock supergroup McBusted kicked off Alive at Delapre on Friday night in front of thousands of fans.
Together, Busted and McFly have sold more than 15 million records worldwide and chalked up 14 number ones, 20 top three singles and 27 top ten singles.
McFly members Tom Fletcher, Danny Jones, Dougie Poynter and Harry Judd joined forces with James Bourne and Matt Willis to form the supergroup in 2013.
Back for its third year, the Saturday will be headlined by Jessie J with Alfie Boe headlining the Sunday.
In just four years, Jessie J has become one of Britain’s most successful female solo singers. She quickly become pop royalty with number one singles and a debut album which has sold millions worldwide.
Alfie Boe’s distinctive voice has helped him conquer the world’s most prestigious opera stages, lead the cast of Les Miserables for nearly a year and wow crowds at the Queen’s Diamond Jubilee Concert.
Boe, who performed at this year’s Royal Variety performance has achieved platinum album sales in the UK and four top ten albums.
Rising soprano star Annette Wardell and the National Symphony Orchestra will support Alfie Boe with VV Brown joining Jessie J.