After the Underworld Court arrive to make one last attempt to banish Grim forever, Mandy insistently makes them reinstate Grim as the Grim Reaper, because he saved them from a future ruled by Boogey, but also because Numbuh 3 was too much of an optimist to actually reap anyone. In the end, a naked, cut up, future Billy appears before them to warn that if Mandy had used Horror's Hand, she would have taken over the world in two weeks, becoming the Lord of Horror from his time. Grim decides to put the hand in his trunk to ensure that that future never comes to pass. Future Billy eventually goes back to the future to make sure that things were set right.