Simon (Kevin Zegers) is a seemingly ordinary biology teacher that spends much of his spare time caring for his Alzheimers mother Helga (Amanda Plummer). This ends up not being the case, as Simon believes himself to be a vampire and spends much of his time looking at online sites for suicidal women who would make for easy prey. One such woman, Jellyfish (Keisha Castle-Hughes), is tricked into believing that she and Simon will both be killing one another, only for Simon to drink her blood after he administers sleeping pills and draws blood from her. Along with his vampiric hobby, Simon tries to keep his mother indoors by putting her in a straitjacket contraption tied to several large balloons. It is when Simon meets Laura (Rachael Leigh Cook) that things begin to unravel, as she grows obsessed with him to the point where she breaks into his home. Things begin to further devolve when Renfield (Trevor Morgan (actor)), a man who also believes himself to be a vampire, emerges onto the scene and is far more violent than Simon ever dared to be.