The Other Side of the Bed

In Madrid, two young couples (Ernesto Alterio and Paz Vega, Guillermo Toledo and Natalia Verbeke) are on a quest to find endless happiness together -- if only each of them could decide who it is they want to end up with. As they trade lovers over and over again, they find none of the bliss they were searching for, and a palpable erotic friction begins to grow between them.