Steven Spielberg’s “Ready Player One” has opened with $3.8 million at 3,500 North American locations in Wednesday night previews.

The sci-fi fantasy is projected to open with $45 million over its four-day opening weekend, which should dominate the domestic box office over the Easter holiday period. Warner Bros.’ “Ready Player One” expands to 4,200 locations Thursday and is launching day and date internationally in 62 markets.

Based on Ernest Cline’s 2011 novel, “Ready Player One” is set both in a dystopian version of Columbus, Ohio, in 2045 and in an elaborate virtual reality world called Oasis to escape the grim reality of the world. The film, written by Cline and Zak Penn, stars Tye Sheridan, Olivia Cooke, Ben Mendelsohn, T.J. Miller, Simon Pegg, and Mark Rylance. Sheridan’s character, Wade Watts, discovers clues to a game within the program that promises the winner full ownership of the Oasis.

Reviews have been mostly positive for “Ready Player One” with a 78% “fresh” score on Rotten Tomatoes. Paramount’s “G.I. Joe: Retaliation” generated $2.6 million in preview showings in Wednesday night previews in 2013 on its way to a $51 million opening on a four-day Easter weekend.

“Ready Player One” is closing out what’s been a downbeat March with the North American box office struggling, off 31% for the same month a year ago, according to comScore. That follows a record February that was driven by Disney-Marvel’s “Black Panther.” The year to date as of March 27 is off 4% at $2.71 billion domestically.

“‘Ready Player One’ enjoyed a solid debut in pre-shows that portend strong opening weekend results,” Paul​ Dergarabedian, a media analyst at comScore, said. “Generally positive reviews and viewer enthusiasm should ensure long term playability for the Spielberg-directed film. The marketplace could use a shot in the arm after a rough month of March that is substantially down vs. last year.”

The second weekend of Universal and Legendary’s “Pacific Rim Uprising,” the seventh weekend of “Black Panther” and Lionsgate-Roadside’s third weekend of “I Can Only Imagine” will be fighting for second place during the holiday weekend. “Pacific Rim Uprising” has grossed $33 million in its first five days, while “Black Panther” has passed the $635 million mark in 40 days, making it the fifth highest-grossing movie ever in the U.S. Faith-based “I can Only Imagine” has taken in an impressive $41 million in its first dozen days.

“Ready Player One” is getting a one-day jump on two other openers — Lionsgate’s thriller “Tyler Perry’s Acrimony” and Pure Flix’s’ “God’s Not Dead: A Light in Darkness.” “Acrimony,” starring Taraji P. Henson as a revenge-seeking wife, is pegged to launch with $7 million to $11 million at about 2,000 venues. Faith-based “A Light in the Darkness” is forecast to finish around $5 million at 1,685 sites.