Sort of like "Sliding Doors" where there are two different realities and we see both... Here, though, it's more of a science fiction tale as the two from each reality switch places and must live each other's lives. Interesting, but the script doesn't really do much with it and never explains how the switch even occurred. However, there is a nice little twist near the end that I didn't expect. Intelligent and entertaining, but didn't take it as far as it could go.