When Black Mask hires Hawkman's foe the Shadow Thief to break him out of Arkham and assist in the theft of a meteorite, Batman must team up with Hawkman to defeat the villains.
This episode contains examples of:
- Actor Allusion: In this episode, Black Mask team-ups with Shadow Thief and fight against Hawkman. In Justice League Unlimited, both Hawkman and Shadow Thief were voiced by James Remar, who voiced Black Mask in this series.
- Expy: Black Mask's last Number One resembles an older, eyepatch-sporting version of Clover Ewing.
- Unobtainium: The Nth element with its anti-gravity properties. Coincidentally, the only source of it on the entire planet is on display in Gotham's museum.
