Justice League of America Vol. 3: Panic in the Microverse (Rebirth)
Ryan Choi leads the JLA on a rescue mission into the Microverse to rescue his long-lost mentor, Ray Palmer, the original Atom, and unravel the mystery of his disappearance in DC UNIVERSE: REBIRTH #1. But when disaster strikes and the JLA's shrink ship crashes on a strange world, the team encounters a mysterious being who claims a connection to the missing Ray Palmer. But nobody's going anywhere without the help of Shahn-Zi, a sentient planet with the power to find Palmer.
Collects JUSTICE LEAGUE OF AMERICA #12-17.