Based on her disastrous first date with Charles, it was clear that there was more to Jan than met the eye, and it turns out, our instincts were spot on. After the gang found out that Tim had apparently been involved with a woman who was loud in bed, they discovered a sex toy in Tim's apartment. However, they later found out that it was actually a swab for cleaning bassoons, and who just so happens to be a professional bassoon player? Yep, that's right! It was Jan all along.
By the season finale, she admits to Charles that she's the killer and even attempts to poison him. However, Charles was already on to her, so she doesn't succeed. But Jan doesn't stop there! She ends up leaking gas into the building in an attempt to kill the gang in the basement for everything they know, but Mabel takes matters into her own hands and punches her in the face. Shortly after, the police arrive and Jan is arrested for Tim's murder.
