Justice Underground is one of the supporting teams in Batman: The Brave and the Bold.
On Earth 3, evil is the dominant power. A rare few indulge in acts of the common good. One man, the Red Hood, was able to convince several to join his cause against the Injustice Syndicate of Amerika as the Justice Underground. They are parallel versions of Black Manta, Dr. Polaris, Clock King, Kite Man, Gorilla Grodd, Sinestro, Gentleman Ghost, and the Brain. However, they were overwhelmed and defeated by the Syndicate. The Red Hood retreated and was able to send for help to Earth 23. A Batman arrived and engineered a series of events that led to the heroes' escape from detention cells in Owlman's Eyrie of Evil. A rematch between heroes and villains took place that favored Red Hood's team.