W&K London will produce nine TV spots supporting and promoting a UK-wide series of events, which Nike is organising to encourage kids to express themselves through sport.
The first tranche of ads will feature kids doing cool moves and showing their skills in both football and basketball, in a bid to get people to the events.
Events will be held in London, Manchester and five other cities to attract kids, with competitions being held to find the best freestyler. Participants will be asked to showcase their moves in front of a crowd.
In a tie-up with the music channel MTV, four winners will face-off against each other and appear in their own Nike freestyle ad on MTV.
All ads will showcase a number of freestylers doing tricks together in up to 36 boxes filling the TV screen, which will move and change shape throughout the spot.
"MTV is not the easiest medium in the world to stand out in, so that's why we opted for something that is simple and graphic," Kim Papworth, the joint creative director at W&K London, said.
Nike's media planning and buying agency, MindShare, has developed the events to extend the brand reach of the Stickman campaign, created by sister agency Wieden & Kennedy Amsterdam. W&K London's new spots will also incorporate Stickman and some of the campaign's other stars.
Launched in February this year, the Stickman campaign features an animated Stickman taking on athletes including Brazilian football star Ronaldinho, the South Korean master of football acrobatics Mr Woo, and the street basketballer Larry "Bone Collector" Williams.
W&K London's two-month push will now tell the story of the freestyler event, showcase freestyling veterans, and encouraging viewers on MTV to vote for their favourite performer.
Votes can be cast online, via text message or through digital television.
"Interactivity is the key new component in Nike's communications," Malcolm Russell, the business director at MindShare, said. "It offers greater consumer involvement than a conventional campaign and gets the brand closer to the target audience. This format has been used within programming but is under-exploited by advertisers."
The ads were written by Matt Follows, art directed by Chris Groom, and directed by Steve Hudson through Outsider.
The work is the first television activity to run from W&K's London office since Nike's Run London campaign last year.