Darkness of the Heart, Last Hope Remaining is the fifty seventh episode of Yu-Gi-Oh! 5D's.
The duel between Yusei and Rudger continues. Rudger uses Earthbound Immortal Uru and pushes Yusei into a desperate situation. As Yusei begins to suffer and his Life Points begin to diminish, Rudger begins to tell him about the tragic event that involved the Enerdy system, Professor Fudo, and Goodwin. Rudger considers that confiding Yusei the truth should be a parting gift before his death.
This episode finally reveals that Rudger originally was the 5th Signer.