The Heroes went to the docks to investigate a tip off. They found Joker and his goons. The goons were easily subdued, but Joker escaped on a boat. However he was stopped by Aquaman and captured by Batman.
As Batman prepared to interogate Joker, some barrels in the back of a lorry exploded, sending a cloud of toxic gas out towards Gotham City. Martian Manhunter transformed his chemical composition to try and neutralise the gas, but as he entered it, the gas exploded due to the production of magnesium. The magnesium ignited and the explosion damaged a hospital and block of flats, and destroyed a warehouse.
The heroes succesfully evacuated the hospital and the block of flats.
Questioned as to what caused the explosion by Comm. Gordon, the team chose not to answer. They handed over Joker to be taken away to jail.
Martian Manhunter returned to the Watchtower, the rest went to the Batcave.
After debate, the team voted not to expel Martian Manhunter from the League despite his apparent negligence. The next plan of action was decided upon – find out about the barrels.
Almost immediately, word came in that the Metro Tower in Metropolis had been raided, and Martian Manhunter reported an attack on the Watchtower…