One small step for the Gotham villains, one giant leap for clown-kind! That's right...this fashionably vocal clown is headed to space. Turns out there's some old experiment left in the JLA moon base, and Luke Fox has put together a team of former villains to help clean up the mess. Sendin' a buncha villains to the moon...? What could go right? Join me, Killer Frost, Bronze Tiger, Solomon Grundy, and more as we learn to moonwalk and put the X in Task Force XX! Harley Quinn Vol. 4: Task Force XX collects Harley Quinn #18-21, Harley Quinn 2022 Annual #1, and Shadow War Zone #1!