Just Like Heaven (2005)

When David rents his quaint San Francisco apartment, the last thing he expects - or wants - is a roommate. He has only begun to make a complete mess of the place when a pretty but decidedly controlling young woman named Elizabeth suddenly shows up, adamantly insisting the apartment is hers. Changing the locks does nothing to deter Elizabeth, who begins to appear and disappear at will. Convinced she is a ghost, David tries to help Elizabeth cross over to the other side. As they search for the truth about who Elizabeth is and how she came to be in her present state, their relationship deepens.

Official website: http://www.justlikeheaven-themovie.com/