With it being a Shazam movie of course it will feature AP as he is a boy who becomes an adult hero when he shouts "Shazam" but now for the AR.

The movie is a direct sequel to "Lego DC: Batman Family Matters" which had Billy Batson (who appeared in a few scenes) about to become Shazam for first time (him at subway being called). He of course becomes Shazam in the new movie.

Justice League are interested but he fears they might change their mind if they find out his secret identity is a kid.

Meanwhile Mr. Mind (he super intelligent talking Worm) puts together the "Monster society of evil" which is a team of villains that are monster like. They kidnap the Justice League. To brainwash them (Mr. Mind's capability) but adults are hard to do so....but kids are. So they use a gas to turn Batman, superman, flash, wonder woman, and Green lantern (Jessica Cruz) into children. So Shazam must work with the youthened Justice League to stop them.