Arthur (Al Pacino) is a shrewd and capable lawyer who lives and works in the bustling city of Baltimore. Unlike most of his peers who are blinded by greed and can give up their bottom line for money, Arthur always sticks to his own principles of justice, speaks for the little people, and never violates his conscience. Arthur's untaintedness in the mud makes his peers stay away from him and regard him as an alien, but Arthur doesn't care. One day, in court, Arthur offended Judge Henry (John Forsythe), and the two of them had a grudge. Who knows, when Arthur sees Henry again, the latter has become a prisoner for rape and injury. Henry asks Arthur to defend himself. If Arthur does not, it will inevitably have a devastating blow to his future career path.