Christopher Luverne Sieber (born February 18, 1969) is an American actor. He is best known for his roles Kevin Burke in Two of a Kind (American TV series) and Agatha Trunchbull in Matilda the Musical. He was nominated for the Tony Award for Best Featured Actor in a Musical for his portrayal of Sir Dennis Galahad in Spamalot, and Lord Farquaad in Shrek the Musical,