On the eve of the festival celebrating the return of the original
Superman from his long exile in the heart of the sun, the members of Justice Legion A - the mightiest heroes of the year 85,271 - come back in time to invite the greatest heroes of the 20th century - the Justice League of america - to travel to the future and take part in the celebration.
But both teams fall victim to a plot millenia in the making. Stranded in the future, the JLA are hunted as dangerous renegades. Meanwhile, their counterparts in the Justice Legion A must find a cure for a deadly virus they have unwittingly brought into their past - our present - and deal with a traitor in their midst.