batman and mystery inc. visit the riddler at arkham asylum. batman, fred, daphne and velma re-encounter crimson cloak, who releases the other inmates from their cells. the investigators just barely manage to escape their clutches and seal them inside the asylum. as they return to the mystery machine, they are intercepted by harvey and the other mystery analysts (sans aquaman), who attempt to arrest them for the isotope theft due to fake evidence planted in the van. batman and mystery inc. make a run for it.