While it was suggested for a long time that Mel Gibson might be appearing in some capacity after the extended production period meant he had to drop out of the lead role, the expected cameo never materialised. Rumours initially suggested that Gibson would appear as a road drifter - probably the original Max - to reinforce the idea that The Road Warrior is more like a mythical figure and could be more than one person.
Maybe that will happen in one of the inevitable sequels?
There were two returns for Mad Max veterans however. Most notably, Hugh Keays-Byrne, who played the villainous Toecutter in the first Mad Max film turned up again as the Big Bad. Had Justice League come off, this would have presumably been his third outing working with George Miller, who wanted him to play Martian Manhunter in the DC ensemble.
Screenwriter Nick Lathouris also makes his second outing, having had a supporting role in the first movie in 1979.