The Girl Under the Waves(2001)

This movie is a four-character improvisation study about the romantic entanglements among the disparate occupants and visitors to a borrowed New York City apartment. Jonathan forgot that he had invited a girlfriend over. They met recently and have been seeing one another but he forgot about it as soon as he met Savannah. She was going to come over to the apartment in the afternoon as he originally thought it was going to be his for a few days (borrowing from a friend's) but due to conflicts and misunderstandings, Savannah and David (who owned the apartment) were occupied as well. Isabel shows up and they hang out until David throws them out after a heated discussion.