The first day at the UK's V Festival saw the Specials take the stage in the sunshine at Hylands Park, Chelmsford, one of the festival's two venues. The ska punk pioneers played a raucous set that NME called the day's liveliest, but the experience was certainly colored by a surprise guest spot by Amy Winehouse.

A suit-clad Terry Hall formally introduced Winehouse as "our good friend" before the singer strolled on stage in a Specials t-shirt and black jeans for the final two songs of the set. "Alright?" she asked the crowd prior to launching into 'You're Wondering Now,' one of her cover favorites. "What a day, eh? Sun's out, Specials are here. Count yourself lucky." They closed the set with the band's politically-charged 1981 single 'Ghost Town.'

Winehouse had been lying low in St. Lucia for much of 2009. She made a botched appearance at the island's jazz festival in May and canceled a gig at Island Records' 50th anniversary party in London. The Specials, meanwhile, are in the middle of a UK tour that has another 15 stops following this weekend's gig.

The V Festival concludes today with performances from dozens of acts including Katy Perry, Lady Gaga and MGMT. Oasis were set to close the night, but canceled because Liam Gallagher is suffering from viral laryngitis, reports the BBC. Snow Patrol is now doing the honors.

Watch yesterday's performance of 'You're Wondering Now':