This movie's premise is basically BIG as a superhero flick and even includes an homage of the BIG piano. It works well while it's light and doing BIG. It works poorly when it tries to be serious with the superhero part which comes off more cheesy than dramatic. Part of the problem is that despite an interesting origin story, antagonist Dr. Thaddeus Sivana is a completely one-note evil dude. Mark Strong is a good actor who is given nothing to do except be a generic villain. The movie even makes fun of this when he begins monologuing and the film keeps cutting out what he's saying it's so generic. Perhaps a case could be made that the writers purposely made him a bad villain, but purposely bad is still bad.
Djimon Hounsou as the wizard Shazam and Grace Fulton as Mary don't fare much better in dull supporting roles, but the three leads shine. Jack Dylan Grazer as Freddie Freeman, Asher Angel as Billy Batson, and Zachary Levi as his superhero alter ego (alternately called the Red Cyclone, Captain Sparklefingers, and Thundercrack but never Shazam or Captain Marvel) all pull off difficult parts and entertaining to watch.
With a budget around $100 million, SHAZAM! is lower than many superhero movies these days, and it shows. The F/X is mediocre when it comes to bringing the Seven Deadly Sins to life, and the set pieces lack pizzazz. The costuming is probably intentionally campy, but that doesn't make it good.
The best parts are the human moments revolving around the foster kids and Billy's seeking his mom (whom in reality the authorities would have found really quickly). It's decently funny especially the part of Darla keeping a secret and the bit with the foster kids teleporting into a strip club. An extended joke on Santa Claus however was not funny. Overall, I liked the movie about as much as Marvel's recent CAPTAIN MARVEL, not bad, not great.
It's a GOOD GOOD MOVIE! Super-Great, must-see level, ...depends.
Better than those ...not now, polarizing, etc. But up there with WW and Aq.
I predicted where it was going, what the climax was going to be, ...but I liked the action, the Actors, the humor, moved by Batson's journey to find his mother, and the storyline, by far radically different than Superman, which Shazam should be (I think the General Audience thinks Shazam is a poor-man's version of Supe).
Hopefully, WB will greenlight a sequel and that should be called Shazam family, ...hail to those 60s and 70s DC comics, Superman family, Batman family (Maybe we'll get a 'Dollar movie'). This is the set-up, so the next movie should deal with Mary, Freddy, Darla, etc.
So, go see it, relax and enjoy it.