During the catastrophic events of Tom King's Heroes in Crisis, Poison Ivy was killed, and Harley Quinn holds herself responsible. But when Poison Ivy is resurrected, Harley decides to take care of her best friend, who is now evolving into a creature who is as much flora as she is fauna. Bad-girl BFFs Harley Quinn and Poision Ivy are back togther—but what happens when a newly reformed Harley discovers that Ivy has gone full-on evil? Harley has also been pardoned from the Suicide Squad, so even if the killings at Sanctuary during the events of Heroes in Crisis hadn't already inspired her to be better, the need to stay out of Belle Reve gives her added incentive to stay on the straight and narrow. What, then, is she to do when Poison Ivy reveals she's had enough of the humans who not only killed her, but are destroying the environment day by day? Can Poison Ivy entice Harley to join her in the plant world, or will Harley have to prove herself by stopping whatever plot Ivy is cooking up? From critically acclaimed author Jody Houser comes a story of two best friends fighting over good and evil. Collects Harley Quinn & Poison Ivy #1-6.