Early box office tracking numbers for Marvel's first Phase 3 adventure, Captain America: Civil War, put its opening weekend somewhere between the $175 million to $200 million range. If it debuts on the low end of that spectrum, it would have the third highest opening in MCU history, between Iron Man 3 ($174.4 million) and Avengers: Age of Ultron ($191.2 million). While we'll have to wait until Sunday to see exactly where the movie lands, it has taken in $25 million from Thursday night preview screenings, falling just short of Avengers: Age of Ultron's Thursday tally last year.

Avengers: Age of Ultron debuted last May with $27.6 million in Thursday screenings, en route to its $191.2 million opening. Since Marvel's Civil War failed to surpass Avengers: Age of Ultron on Thursday, it's possible that it may not surpass that movie's opening weekend numbers. However, it's worth noting that Captain America: Civil War is faring better with critics, with a strong 92% Fresh rating on Rotten Tomatoes, compared to Avengers: Age of Ultron's 75% score. Captain America: Civil War did beat Avengers: Age of Ultron in IMAX Thursday screenings, though, posting $3.1 million, barely beating Avengers: Age of Ultron's $3 million gross, according to Deadline.

Avengers: Age of Ultron went on to earn $84.4 million on Friday, a record for the biggest opening day in May. The movie opened in 4,276 theaters, with Captain America 3 slated to debut in 4,226, fifty fewer than Avengers: Age of Ultron. Captain America: Civil War doesn't face any direct competition, but it will also be facing another Disney hit, The Jungle Book, which is believed to take in $20 million in its fourth week in theaters, which may cut into Captain America: Civil War's success. The Jungle Book has currently earned $263.1 million domestically through its three-week theatrical run.

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Captain America: Civil War is already a hit internationally, taking in $291.2 million in select markets over the past week, with the movie also opening in Russia, China and Argentina this weekend. It's expected to cross the $300 million mark internationally at some point later today. The international grosses have already made the movie profitable, with Marvel spending a whopping $250 million to make this superhero extravaganza, which splits the Marvel Cinematic Universe in half in an epic battle. This movie features practically every superhero character that has already been established in the MCU, with the exceptions of Thor (Chris Hemsworth) and Hulk (Mark Ruffalo).

Avengers: Age of Ultron's opening weekend gross represented 41.7% of its total domestic take of $459 million, and it took in an additional $946.4 million internationally for a worldwide total of $1.4 billion. Only three of Marvel's 12 movies have passed $1 billion worldwide, Iron Man 3 ($1.2 million), Avengers: Age of Ultron ($1.4 million) and The Avengers ($1.5 million). We'll have to wait and see if Captain America: Civil War can beat those numbers, so be sure to check back on Sunday for the box office estimates.