Possible Worlds is a 2000 Canadian drama film directed by Robert Lepage combining of art and science and the theme of diverse, multilayered identity. George Barber (Tom McCamus) is a mathematician having strange dreams. He continuously meets a woman, Joyce (Tilda Swinton), at a bar. Sometimes, she is a scientist, sometimes she is a stockbroker, and she doesn't seem to remember him from a moment to another. He has also a dream about strange men who move stones here and there on a rocky waterfront. There is a man in this dream, the Guide (Gabriel Gascon), who is also a neuroscientist in real life.
