Jesse (Ethan Hawke) meets the beautiful Celine (Julie Delpy) on a train in Europe and both decide to spend one day and night together in Vienna. They spend the day exploring the city and getting to know each other. Their mutual attraction grows because of the freedom of knowing they may never meet again. As day turns into night, their relationship has some tests but seems to blossom. The angst of their attraction and fear of what will happen in the morning only serves to bond the two even more. Falling for each other, they have a one night stand, despite knowing they will lose each other at dawn. Now, they have to decide if this is true love or truly a one night stand.