In its early days, the DC Extended Universe was criticized for being too dark and dreary with a mopey Superman and a murderous Batman. To that end, Shazam! seems like a response to the DCEU’s critics as a lighthearted romp that feels like a full-blown comedy. Zachary Levi described it as Big with superpowers.

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The story concerns 13-year-old Billy Batson, who is given the ability to turn into an adult superhero with the titular code word. With any luck, we have more DCEU movies like this to look forward to. Here are 10 interesting details from the making of Shazam!.

John Cena Met With David F. Sandberg About Playing Shazam

John Cena in Bumblebee

Director David F. Sandberg met with John Cena about possibly playing the role of Shazam, but Cena was ultimately unable to take the role as the shooting schedule of Shazam! clashed with his commitments to Transformers spin-off Bumblebee.

So, Zachary Levi was able to clinch the part. Cena will instead join the DCEU in a different role in James Gunn’s upcoming Suicide Squad sequel/reboot.

The Failure Of Speed Racer Delayed This Movie’s Initial Development

The poster for Speed Racer (2008)

In the 2000s, a Shazam! movie was in development with a script by John August. However, in 2008, the Wachowskis’ Speed Racer movie bombed at the box office with a light tone and The Dark Knight became a huge hit with a dark tone, so Warner Bros. called off Shazam! and focused on darker comic book movies instead.

Ironically, Shazam! would later get made when the failure of Batman v Superman and Justice League had Warner Bros. scrambling for lighter superhero fare.

Henry Cavill Was Supposed To Cameo As Superman

Henry Cavill as Superman stands on a Smallville street

DC fans were pleasantly surprised by Superman’s appearance at the end of Shazam!, but they were also confused by the fact that he doesn’t show his face. Apparently, a cameo was part of Henry Cavill's contract renegotiations, and ultimately fell through. So, Superman’s face is hidden and he’s played by Zachary Levi’s stunt double Ryan Handley.

RELATED: Superman: 5 Reasons Henry Cavill Should Be Replaced (& 5 Why He Should Stay In The Role)

Zachary Levi Packed On 20lbs Of Muscle For The Movie

Zachary Levi as Billy Batson in Shazam

As with any actor who’s cast to play a superhero in a high-profile blockbuster, Zachary Levi worked out extensively to bulk up for Shazam!, adding 20lbs of muscle to his frame. This raised his overall body weight to 220lbs.

In an interview, producer Michael Rosenbaum guessed Levi’s post-workout weight to be 215lbs, and Levi was quick to correct him and tell him that he was 5lbs short.

Sam Raimi Wanted To Direct Shazam!

Sam Raimi on the set of Spider-Man

Before David F. Sandberg was tapped to direct Shazam!, a different horror director, Sam Raimi of The Evil Dead, expressed interest in helming the project.

Raimi is no stranger to comic book movies. He developed a Thor movie in the ‘90s before directing Tobey Maguire’s Spider-Man trilogy, and he’s been hired to helm the next Doctor Strange movie.

Michael Keaton Was Considered To Play The Wizard

Michael Keaton in the Batsuit in Batman Returns

Djimon Hounsou ended up playing the Wizard in Shazam! after appearing in four other comic book movies: Guardians of the Galaxy, Captain Marvel, Aquaman, and Constantine. But he wasn’t the producers’ first choice for the character.

Ron Cephas Jones was originally cast in the part, but had to drop out due to scheduling conflicts with This is Us. Before Hounsou was cast, the producers approached former Batman Michael Keaton, Alan Alda, F. Murray Abraham, and Tony Shalhoub.

Director David F. Sandberg Cameoed As Five Different Characters

Shazam Set Photo with David Sandberg

It’s not uncommon for directors to make cameo appearances in their movies, ever since Hitchcock famously showed up in every single one of his works. But in Shazam!, David F. Sandberg cameos as five different characters.

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He voiced Mister Mind in the mid-credits scene and Marilyn Batson’s boyfriend when Billy goes to her apartment, as well as all three Crocodile-Men with the help of puppeteers Neil Morrill and Steve Newburn.

Dr. Sivana Had A Daughter In Early Drafts Of The Script

Shazam Doctor Sivana Mark Strong

In early drafts of the script for Shazam!, Dr. Sivana had a daughter named Beautia Sivana, as he does in the comics. The producers narrowed down the casting shortlist to Virginia Gardner, Hunter King, and Tori Anderson before the role was cut from the movie.

Zachary Levi Improvised A Bunch Of His Lines

A bunch of Shazam’s funniest lines were improvised by Zachary Levi, who clearly relished the chance to play a superhero with the mind and soul of an overzealous 13-year-old kid. These ad-libs included the “Detective Moron” and “You’re dead” gags, as well as the line “Get him, Batman!” during the toy store fight.

Dwayne Johnson Was Originally Going To Appear As Black Adam

Black Adam Dwayne The Rock Johnson

This movie was originally going to feature an appearance by Billy Batson’s greatest foe, Black Adam, but his scenes were ultimately cut when the powers that be in charge of the DCEU decided to save him for his own solo movie.

Dwayne Johnson has been cast in the role, which may have contributed to the decision to give him his own movie, since Johnson is one of the only movie stars working today who can still draw a crowd based on their involvement alone.

NEXT: Black Adam: 5 Things That Have Been Confirmed (& 5 Fan Theories)