Blake and his friends return from Gateway City for a final showdown with Xander the Enigma, with only one chance to save Underworld City. and the world up top.

After the final, reality shaking killing in Underworld City, each world on the bank of the River Styx teeters on the brink of catastrophe. Out of options, Blake is forced to go further than he ever has before... down the river to lands beyond the Underworld.

The escape of Collin Morrow and a shocking death send the entire team up top into a tailspin, and force Blake and Conrad to face a deadly labyrinth in Underworld City as a last chance to save a soul and find a clue that can help them thwart their powerful adversary. Presented in Dolby Atmos for a...