Lobo invades the world of Injustice in 'The Main Man Among Us.' When Superman's world was cruelly taken from him, his retribution was swift. But one of the perpetrators is still out there, and her freedom gnaws at him. But The Man of Steel can't spend time tracking down one person-not when the entire world needs him. So he enlists the help of Lobo, one of the greatest bounty hunters in the universe, to track down a now super-powered Harley Quinn!