The campaign, created by CHI & Partners, is the brand's first TV spot and comes as part of a wider overhaul in response to slow growth.
The ad, which breaks on 13 May, pushes the mental benefits of staying hydrated. It shows the 70s puppet showcasing intricate dance moves, stopping only to rehydrate. It closes with the endline: "Brains perform best when hydrated."
The ad was written and art directed by Ewan Paterson and directed by Ringan Ledwidge through Rattling Stick.
The campaign is supported by a digital test that allows people to make Brains dance using their webcam or keyboard. It then rates users' alertness, memory and concentration with the winners netting a free MP3 download of Rhythm is a Dancer.