"Cocoon" was the third and final single from singer Björk's album Vespertine. It was written by Björk and Thomas Knak, and mixed by Mark "Spike" Stent. The song is a low-key musing about a girl basking in the glow of a romance that has taken her by surprise, and includes frank sexual narrative related both explicitly and through euphemism and metaphor. The single peaked at number 35 on the UK Singles Chart.
The music video was nearly as controversial as the previous one for "Pagan Poetry". The "Cocoon" video was directed by Eiko Ishioka. It shows Björk, apparently naked (though actually wearing a very close fitting 'nude' body suit), with her hair styled to resemble a geisha. She is on her own under a simple spotlight, before red threads start emerging from out of her nipples. Throughout the video, she is found playing with the threads before they eventually develop a cocoon around her, until she is completely cocooned. Like the video for "Pagan Poetry", it was banned from prime-time MTV.