Gary the Rat (2003)

Gary Andrews is a ruthless lawyer who has devoted himself to winning the Rat Race of life. As it turns, he has been so successful at it that one night, he mysteriously changed into a humanoid rat for real. Now, Gary must struggle to live with this bizarre condition to live his life even while he resists the suggestion that changing his ways may be the only way to change back. Unknown to Gary however, one of his neighbouring tenants has hired an insane exterminator, Johnny Horatio Bugz, to kill him although Bugz has far more determination than competence.