WARNING: The following article contains spoilers for Shazam!, in theaters now.
As much as Shazam! is a standalone entry in Warner Bros.' so-called DC Extended Universe, it also pays tribute to the superhero films that came before it. The plot doesn't connect to those movies, but director David F. Sandberg includes a lot of homages to them, as well as the comic book source material, and earlier adaptations.
Here we break down biggest nods in Shazam! to DC comics and the larger DC Extended Universe.
THE AQUAMAN LOVE
Freddy Freeman (Jack Dylan Grazer) is a huge fan of Aquaman. In several scenes, he even wears T-shirts bearing the hero's movie logo. He takes that devotion into overdrive in the post-credits scene, as he and Shazam test whether the hero possesses Aquaman's powers, by trying to communicate with a goldfish in their bedroom, with no success.
THE BATMAN FANBOY
Freddy is also obsessed with the Dark Knight, and owns several Batman tees, a book bag, and even a Batarang, all emblazoned with the symbol of Ben Affleck's vigilante. To top it off, when Freddy and Shazam try to secure a loan for a lair, they basically describe the Batcave and its waterfall entrance. Later, in the toy store scene, Zachary Levi's Shazam throws a Batman toy (with Kevin Conroy's voice) at Mark Strong's Doctor Sivana. We can even quickly spot Jim Gordon's Batman mech suit from the "Superheavy" comic book arc among the plethora of DCEU action figures.
THE SUPERMAN SYNDROME
Freddy's memorabilia collection features newspaper clippings, including an article from Richard Donner's Superman, with the headline "Caped Wonder Stuns The City," and bullet casings. There's also a Time magazine showcasing Zod's invasion from Man of Steel.
Throughout the film, Shazam references Superman's powers, most notably flight, but the kicker comes at the very end when he brings Superman to meet Freddy at school, accompanied by John Williams' iconic theme. As a bonus, Sivana's father is played by John Glover, who who portrayed Lex Luthor's dad on Smallville.
THE ROCK OF ETERNITY'S RELICS
Before the Rock of Eternity is pillaged by Sivana and the Seven Deadly Sins, we can spot Mister Mind, the alien worm, in his glass jar. A classic villain from the comics, he's positioned in the mid-credits scene to the antagonist in a potential movie sequel. We can also spot the Magic Mirror from DC's New 52 era, which contained Billy's supernatural ally, Francesca. There's also the magic wand called the The Ibistick of Ibis, and the Burning Violin from the 1946's Captain Marvel Adventures #64, in which another fallen pupil of the wizard turned into a weapon of mass destruction.
THE WATCHMEN TEASE
It's worth mentioning that when Asher Angel's Billy is reprimanded by a social worker for tricking the police and stealing information from them, there are cups, pins and other merchandise on her desk, which Sandberg admitted are nods to the iconic smiley face from Alan Moore and Dave Gibbons' seminal Watchmen miniseries.
THE CROCODILE MEN
In the aforementioned scene, we glimpse a crocodile action figure on the social worker's desk, which seems to be a tribute to the Crocodile Men Billy fought in his Captain Marvel days. These beasts get an even bigger plug later on, when Shazam and his siblings open a door in the Rock of Eternity to another dimension, only to find them playing poker. That's also a nod to the villainous Sobek, who played a crucial role in Black Adam's war against the hero in the modern comics.
OLD SCHOOL BILLY
The movie also pays tribute to Fawcett Comics, the original publisher of Shazam, then known as Captain Marvel. Although the film is set in Philadelphia, just like the recent comics, the kids attend Fawcett Central High School.
The ode to the bygone era continues as Shazam yells his signature catchphrase Holy Moly!" when he tries to catch a bus that falls off the freeway. Billy also carries a backpack emblazoned with a tiger emblem, a reference to Tawky Tawny, the sharp-dressed, anthropomorphic tiger that was part of so many of the hero's early adventures.
ACE CHEMICALS PLUG
Near the abandoned warehouse where Freddy trains Billy and records his powers, we can spot Ace Chemicals in the background. That's the name of the factory where a member of the Red Hood Gang fell into a vat of chemicals after tussling with Batman, resulting in the creation of The Joker.
In the comics, the Monsterlands is one of seven magical realms the champions of Shazam were meant to guard, to prevent the monsters locked inside from eascaping. When Billy's siblings open doors in the Rock of Eternity in Shazam!, one leads to a foggy marshland, from which a vine-like creature attacks. That appears to be a nod to that beastly realm.
R.I.P. JUSTICE LEAGUE: MORTAL
George Miller's Justice League: Mortal began casting in 2007, only to be shelved by Warner Bros. on the eve of principal photography. Oddly enough, two actors from that film end up with roles in Shazam! Adam Brody, who was cast as The Flash, plays the super-powered version of Freddy, while D.J. Cotrona, who was cast as Superman, appears as the upgraded version of Pedro, both created a result of Billy sharing his powers with his siblings in hopes of defeating Sivana.
BLACK ADAM THROWS DOWN
Dwayne Johnson has been attached to the role of Black Adam for some time, but while he doesn't have an actual cameo in Shazam!, the wizard shows Billy a holographic presentation that depicts his former champion being corrupted by power ages ago. It's easy to recognize this is Black Adam, the iconic fallen apprentice who could well return to challenge Billy for the mantle of "Chosen One."
Directed by David F. Sandberg, Shazam! stars Asher Angel as Billy Batson, Zachary Levi as Shazam, Mark Strong as Dr. Thaddeus Sivana, Djimon Hounsou as the ancient wizard Shazam, Grace Fulton as Mary Bromfield, Jack Dylan Grazer as Frederick “Freddy” Freeman, Ian Chen as Eugene Choi, Jovan Armand as Pedro Peña, Faithe Herman as Darla Dudley, Cooper Andrews as Victor Vásquez and Marta Milans as Rosa Vásquez.