Alice Pieszecki, played by Leisha Hailey, is one of the leads of the Showtime series The L Word.
One of the first things that we learn about her is that she is bi. In the pilot, a group of lesbian women are talking about the fact that a donor's sperm is not going to work for inception.
Alice: Oh my god, you would never know it by the way he fucks
Dana: Christ, Alice. When are you going to make up your mind between dick and pussy? And spare us the gory bisexual details.
Alice: Well for your information, Dana, I'm looking for the same qualities in a man as I am in a woman.
She begins the series as a journalist writing for LA Magazine, she writes mostly "best of articles", which is running joke for the beginning of the series.
In the first season, she talks about her craving for a man and pursues relationships with men.
She goes on to date men and women and male lesbian throughout the first few seasons. However as time goes on her behavior when she's in a relationship becomes increasingly insane. She stalks a partner and decides that she can only feel that kind of insane love for women and that therefore she is not bi.
Alice falls victim to the common fallacy that a person must feel the same type of attraction to both men and women in order to be bi.