April 5 (UPI) -- Mark Strong said he signed on to star in Shazam! because he loved the idea of playing a super-powered bad guy in a comic-book movie helmed by a horror filmmaker.
"I've played a lot of villains in my time, but I thought this was a particularly good one because he gets to fly. He gets to fire electricity out of his hands," the 55-year-old British actor told UPI in a recent phone interview.
Collaborating with Lights Out and Annabelle: Creation director David F. Sandberg was a bonus.
"I knew I was in safe hands as far as how spooky and creepy and dangerous and evil Sivana would end up being," added the Kingsman, Syriana and Sherlock Holmes actor.
Set to open in theaters Friday, the PG 13-rated and critically acclaimed Shazam! depicts what happens when the titular wizard (played by Djimon Hounsou) tests the mettle of 14-year-old foster child Billy Batson (played by Asher Angel,) likes what he sees and bestows upon him extraordinary powers, including the ability to transform into a muscular adult man (played by Zachary Levi) when he shouts "Shazam!"
Years earlier, the sorcerer had also interviewed Strong's Thaddeus Sivana as a young boy (played by Ethan Pugiotto,) but dismissed him after determining he was not pure of heart.
Resentful Sivana grows up to be a physicist who devotes his intelligence -- and the resources of his wealthy, estranged family -- to studying the magical realm, ultimately returning to battle the wizard and take control of the spiritual embodiments of the seven deadly sins.
A sense of balance permeates the film, with the rivals both surviving childhood traumas.
While Billy eventually finds love with adoptive parents and siblings (played by Cooper Andrews, Marta Milans, Jack Dylan Grazer, Grace Fulton, Ian Chen, Faithe Herman and Jovan Armand) in Philadelphia, Sivana feels lonely and betrayed by his father and brother (played by John Glover and Wayne Ward.)
"There's that theme at the center of the film, which is family. Where do we belong?" Strong said.
The experiences Sivana and Billy have with those closest to them impact the choices they make and what they do with their special abilities when they acquire them.
"It's very unusual that you get the backstory of the villains. Obviously, [the two characters] being given the same choice -- whether to go to the good or the bad side -- I thought was really quite interesting," Strong said. "You need a villain, otherwise you can't have a hero."
Not satisfied with the power the sin spirits afford him, the grown-up Sivana sets out to steal Billy's capabilities, as well.
"It's never enough. He wants all of the power and more," Strong said. "In Western culture, the hero has to vanquish the villain, so the villain normally gorges himself and ends up imploding because he overdoes it."
Sivana -- who starts out as an imaginative and vulnerable child -- has several chances as an adult to grant forgiveness or mercy to others, but doesn't.
The hardness of his heart suggests how high the stakes are for Billy and the people about whom he cares.
"The more we love the hero and the more fun we have with his interactions with all the other kids and the more we laugh at that and feel comfortable with that, the more necessary it is to have a dark side that is truly terrifying. So you really do feel like the people you are falling in love with are in danger," Strong said.
The younger members of the Zero Dark Thirty and The Imitation Game actor's family are excited to see Shazam!, partly because Strong is in it and partly because the previews have been so enticing.
"I've done a lot of movies in which I have been so horrible, they can't see it," he said. "But this one they can see and I know that they are really looking forward to because they absolutely love the trailers."
"I get to play a good guy in it for once," he said. "It's not based on real people, but it is based on the realities of the First World War."
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