Last weekend saw Sony's Spider-Man: Into the Spider-Verse ride a big wave of buzz to the top of the box office with a $35.3 million haul. However, this weekend it's going to be a new hero on top as the King of Atlantis, aka Aquaman, is riding his own wave of buzz into theaters and will also be crowned the king of the box office. But this is going to be one of the most competitive and important weekends at the box office all year, as both Mary Poppins Returns and Bumblebee are also set to arrive for the pre-Christmas frame.

Aquaman, which brings back Jason Momoa in the titular role following his turn in last year's Justice League, will win the weekend, with box office estimates on the low end at $65 million. But that number seems conservative and it's likely that DC's latest will be closer to the mid $70 million range, if not even managing to eclipse $80 million. The movie, directed by James Wan, has already opened overseas to more than $266 million.

Next up is Disney's highly-anticipated sequel Mary Poppins Returns, which sees Emily Blunt as the magical, musical nanny, originally played by Julie Andrews. Disney is getting a head start on things as the movie arrives today and projections have it bringing in between $50 and $60 million over the seven-day debut leading up to Christmas. It should see a weekend total of between $30 and $40 million, which will be good enough for the number two spot.

Paramount is releasing Bumblebee this weekend, which is a very important moment for the Transformers franchise. The Last Knight took a huge nose dive at the box office last year and, so it seems, moviegoers had had enough of what Michael Bay had to offer in this department. So, Travis Knight (Kubo and the Two Strings) came in to tell a very different kind of story set in the 80s. So far, critics have been kind, as the spin-off boasts a very solid 96 percent on Rotten Tomatoes. Unfortunately, it's only going to make enough for third place with around $30 million.

However, good word of mouth could carry this one far and it's perhaps more important to have a good movie at this point to help instill confidence in moviegoers for the future. What's interesting is that neither Paramount nor Warner Bros. were willing to budge from the December 21 release date. Aquaman is going to win the day, but might both movies have benefited with some space between one another?

Rounding out the top five will be a pair of holdovers. Spider-Man: Into the Spider-Verse is still riding high and should grab another $20 million or so, which will put it in fourth place. Clint Eastwood's real-life drug cartel drama The Mule will finish in fifth with between $10 and $12 million. Also of note; Robert Zemeckis' Welcome to Marwen opening and will nab around $5 million and Peter Jackson's Mortal Engines, already one of the biggest bombs of the year, may not even make the top 10 in its second weekend. Be sure to check out our full list of weekend box office predictions below and check back with us Sunday for the top ten estimates. These numbers were provided by Box Office Mojo.