We're still three weeks away from the release of Christopher Nolan's shadowy movie Interstellar, but speculation is already hotting up regarding the potential of this big-budget sci-fi epic. The plot remains a mystery - other than the fact that it will include ecological cataclysms and wormholes - and it's that intrigue that is driving the growing publicity campaign.

Interstellar Matthew Mcconaughey will be a big draw, though Christopher Nolan is becoming a brand in himself

As Variety notes, Nolan has essentially become a brand in himself - a tag that could previously only be attributed to Spielberg and Scorsese - and Interstellar is tracking to make more than $50 million as word-of-mouth increases. Last year, Gravity opened to $55.8 million and Legendary Pictures have a similar number in sight.

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Fandango is reporting that pre-sales for the movie are outpacing those of Inception and Dawn of the Planet of the Apes - which debuted to $62.8 million and $72.6 million respectively. 

Watch the trailer for 'Interstellar':

"I fully expect to be sold out through the weekend," said Tom Stephenson, CEO of Look Cinemas, which is reporting that Tuesday and Wednesday night screenings for Interstellar are already booked up. "I'm a big Chris Nolan fan, so I expected the response would be great, but to have sell outs this early is incredible."

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The movie, which cost $165 million to make, stars Matthew McConaughey, Anne Hathaway and Jessica Chastain. It will be projected digitally, but also in 35mm and 70mm formats, as well as Imax 70mm. 

"You want to see it right," said Alwyn Hight Kushner, president and COO of the TCL Chinese Theatre. "This is a big event movie. You can't watch it on a TV screen. It's not a Netflix movie. It's a real film that you need to see in cinemas."

Imax theaters will also be showing Interstellar 3.00am and 3.30am screenings on Wednesday, to keep up with demand.

Anne Hathaway