THE CHALLENGERS FACE A DEEP SEA MYSTERY! The odyssey of the Challengers continues on the Watchtower and beyond! Bracing under the strict oversight of Mister Terrific in their investigation into the Godshock and still reeling from something Unknown rattling them all internally, it's June's turn to be shaken to the core when a strange rupture in the deepest part of the ocean draws the League's scrutiny... and awakens the most difficult creation of her Challenger past. Guest starring Batman, Aquaman, and the Sea Devils!