Dizzee Rascal opens main stage at Radio 1's Big Weekend
Dizzee Rascal has opened the main stage at Radio 1's Big Weekend in Londonderry.
The rapper duetted with Robbie Williams on stage - the first time they have performed their forthcoming single, Goin' Crazy, together live.
"We smacked it, just the energy as soon as we got on, it was crazy," the rapper said.
"It was wired. I can't ask for much more than that." He added, "It's Robbie Williams isn't it!"
Calvin Harris is the first headliner for the three-day event in Derry's Ebrington Square.
Friday's line-up will focus on dance music and BBC Radio 1Xtra with acts like Rita Ora and Chase and Status.
Tickets for the festival have already been allocated. Gates to the event opened at around 3pm (15:00 BST).
Gates will open at around midday in Derry on both Saturday and Sunday, 25 and 26 May.
The event finishes around midnight on Friday and around 11.30pm on Saturday and Sunday.
Biffy Clyro headline the Main Stage on Saturday night, with Bruno Mars closing the show on Sunday night.
Other acts performing across the weekend include Olly Murs, The Vaccines and Foals.
Wretch 32 is performing on the Main Stage on Sunday.
He said: "Big Weekend is the first festival I ever went to in my life when it was held in Swindon so to be asked to come back on the bill, I'm absolutely ecstatic."
Mercury Music Prize winners alt-J are also performing. Drummer Thom Green said: "I can't wait. We love Radio 1 and to be involved in the festival is great."
Jake Bugg's on the main stage on Sunday and said: "In Derry, they're not spoilt for music so I think the crowd will be quite appreciative."
He also said he'd change his set according to the mood of the crowd.
"If everyone's talking there's no point playing a soft song, give them a tune they can dance to."
Others to perform on Sunday include The Script and Macklemore & Ryan Lewis, whose single Thrift Shop is the best-selling of 2013 so far.
There's more information on BBC Radio 1's Big Weekend Derry-Londonderry website.
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