Liam is a werewolf and a former resident of the Oldham Psychiatric Institute. He killed his best friend Joe when he suddenly and unexpectedly turned into a werewolf. According to Alistair, he thought they could live 'the old way': without medication and with transformation. He was drugged by Lillian to set an example to the other residents that they could not.
While still transformed, he jumped out Joe's bedroom window and roamed the countryside, until he eventually came across Will Zimmerman who calmed him down. He helped Will to get back inside, but refused to go back himself.