Zack Snyder's "Man of Steel" is well on its way to a predicted $100 million opening weekend as Variety reports midnight box office numbers of $21 million, with $12 million earned from Walmart's special 7:00 PM ticket package. Although "Man of Steel" beat out the midnight openings of both "Iron Man 3" ($15.6 million) and "The Avengers" ($18.7 million), it was unable to surpass one of the highest midnight-grossing comic book films: Christopher Nolan's "The Dark Knight Rises" ($30 million).

"Man of Steel" is expected to reach $100 million by the end of its opening weekend, and the strong midnight numbers are a good start to that total. If the Superman reboot were to hit the magic number, it would be among only 24 films to have done so. Strong first weekend numbers are rumored to have a large impact on Warner Bros. moving forward on a "Justice League" film, although the studio has already fast-tracked a sequel.

"Man of Steel," which cost about $225 million to produce and another $150 million or more to market and release, stars Henry Cavill as Superman/Clark Kent, Amy Adams as Lois Lane, Michael Shannon as Zod, Kevin Costner as Jonathan Kent, Diane Lane as Martha Kent, Russell Crowe as Jor-El, Ayelet Zurer as Lara Lor-Van, Antje Traue as Faora, Laurence Fishburne as Perry White, Christopher Meloni as Colonel Hardy, Harry Lennix as General Swanwick, Michael Kelly as Steve Lombard and Richard Schiff as Dr. Emil Hamilton.