The nerdy, obsessive guy becomes much cooler somehow and writes a popular play or something like that. The original girl he was obsessed with then decides after seeing his play that she likes him after all But he's already gained a girlfriend so she becomes slightly obsessed with him.
If I remember right it's kind of a dark comedy because there are a number of lighthearted moments but at the same time some dark things happen in it.
If anyone can help me I'd really appreciate it. I know it's not a big blockbuster but maybe someone will of heard of it. Thanks a lot :-)