The press ad, created by Quiet Storm, features a line of people. Under each person is a name, but on closer reading, it says: "Sadie girlfriend of Paul who sees Wayne son of Derek lover of Mike father of Zac brother of Trish who fancies Simon and Tara lover of Terri who was Terrence ex of Annaki sister of Will boyfriend of Steve ... are all going to the BT Main Dance Tent".
The campaign fits in with BT's mainstream advertising, which uses the "bringing people together" strapline.
It follows on from Quiet Storm's "Ron and Roger" campaign last year, which featured a dour-looking couple transformed by the cowboy outfits they sport when attending the festival.
The event is held in Hyde Park on July 26, with some 90,000 visitors expected to attend.
Caroline Waters, director of people networks for the BT Group, said: "Our relationship with Quiet Storm goes from strength to strength -- its creativity and empathy with the big issues of business and society are unique.
"Bringing people together is absolutely aligned to BT's vision of connecting everyone's world and is a tremendously innovative way of reaching out to new customers."
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