The Young Chasers four-piece will join the trio at their Alexandra Palace gigs.
Two Door Cinema Club
Two Door Cinema Club Biography
Northen Irish indie rockers Two Door CInema Club formed in 2007 and are: Alex Trimble (vocals, guitar), Sam Halliday (lead guitar) and Kevin Baird (bass).
Debut album 'Tourist History' arrived in 2010, followed by 'Beacon' in 2012 and have recently started work on their third studio album, to be released in 2015.
Jamiroquai is also set to top the bill at the Cornish festival, which takes place from 9-13 August.
The Northern Irish band told Radio X they were in shock over the news ahead of their slot at the Pyramid Stage.
Sam and Alex from the band sat down with Radio X for a catch up before their performance in Poland...
It's Jam bassist Bruce Foxton's birthday, so, let us celebrate the joy of the three piece with a look at the finest trios in rock and roll.
Cast your mind back to the year of Total Life Forever, The Suburbs, Come Around Sundown and The Naked And Famous.
Two Door Cinema Club: Top Three Downloads
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