DC Universe Rebirth Tie-in - The Poison Truth: Part 5 of 6 - Written by Simon Oliver. Art by Pia Guerra. Cover by John Cassaday. John's gotten the djinn off his back, at least for the moment. Now he needs Mercury. As they leave English shores behind, it's time for a heart-to-heart as Mercury tells John what happened to her while Swamp Thing was battling the Rot.