Walt Disney Co.’s upcoming “Star Wars” movie is awakening a global force of fans who are swamping websites in the U.S. and U.K. as they try to reserve seats to a movie still two months away from opening.

The U.S. ticketing sites Fandango and MovieTickets.com struggled to keep up with demand, as Disney’s ESPN network kicked off early sales with a new trailer for the film during a “Monday Night Football” telecast. Attempts on Fandango to buy tickets to the movie, which opens on Dec. 18, produced the notice “Error 500: Technical Difficulties.”

“Something funny is definitely going on,” the site said. “We’re getting to the bottom of it.” Officials at Fandango, owned by Comcast Corp. didn’t respond to requests for comment.

Cinema chains are being tested globally by demand for the seventh installment in the saga, projected to be one of the top-grossing pictures of the year, if not all time. “Star Wars: The Force Awakens” is the first in the series from Disney, which acquired franchise-owner Lucasfilm Ltd. for $4 billion in 2012. Earlier on Monday, Odeon & UCI Cinemas Group said online ticket sales for “Star Wars” set a record for the U.K. chain and caused booking delays at its website.

The U.K.’s Vue Entertainment Ltd. also had record advance ticket sales purchases, selling 10,000 in the first 90 minutes, according to an e-mailed statement. Customers were able to purchase throughout the day with only a few delays.

“We’ve seen massive traffic to our website today as guests book ahead” for “Star Wars” and the new James Bond film “Spectre,” Simon Soffe, an Odeon & UCI spokesman, said Monday in an e-mail. The chain is owned by Guy Hands’s Terra Firma Capital Partners Ltd., while Vue’s parent is Omers Private Equity.

In the U.S., Twitter users reported trouble reaching the Fandango site, as well as those of some cinema chains. Another ticketing website, Movietickets.com, was working long enough for “The Force Awakens” to become its No. 1 seller with 44% of tickets sold in the prior 24 hours. But then its site too succumbed, posting this message: “Web server is returning an unknown error.”

Morgan Stanley analyst Benjamin Swinburne said in June that the movie could be the third highest-grossing film in history. He estimated “The Force Awakens” will take in $1.95 billion in ticket sales worldwide. That would place it behind “Avatar” at $2.8 billion and “Titanic” at $2.2 billion, according to data from Boxofficemojo.com.

Selling tickets two months before a film’s debut is a strategy Hollywood has occasionally deployed in the past for its most highly-anticipated releases.

“The Force Awakens,” directed by J.J. Abrams, has revealed itself in two earlier trailers to be very much an homage to the 1977 original, even to the point of including many from the cast.

Disney has been seeding the market for a new generation of fans, showing “Star Wars Rebels,” a cartoon on its Disney XD network, and releasing toys globally last month in a promotion it dubbed “Force Friday.”

Source: Bloomberg