The DVD release of The Dark Knight has seen a spike in the popularity of Blu-Ray, industry experts have confirmed.

The Batman Begins sequel hit the shelves on Monday December 8th and has sold more than 400,000 copies according to midweek sales figures.

While its reaching the number one spot would not be a surprise - given the film's huge success at the box office - the amount of Blu-Ray copies of The Dark Knight sold is certainly a shock.

More than one-fifth of Dark Knight DVDs bought this week have been for the high-definition format, HMV spokesman Gennaro Castaldo confirmed.

"It's one of our fastest-selling DVDs of all time and certainly our biggest Blu-Ray release of all time," he told

Asked about the cause of the high Blu-Ray sales for the comic book blockbuster, Mr Castaldo said fans of the Dark Knight would be aware that "watching Blu-Ray gives it an extra dimension".

"Some people may have gone as far as buying a Blu-Ray player just to watch the film," he added, citing the six IMAX sequences shot by director Christopher Nolan.

However, despite the film's popularity in its first week on release, it will not be the biggest seller of the year, he confirmed.

"The Dark Knight's outselling Mamma Mia! four to one this week and will very comfortably go to number one," Mr Castaldo explained.

"But it's likely Mamma Mia! will displace it the following week and return to the top spot as we believe it's going to be the number one DVD at Christmas."

The biggest-selling DVD ever is Titanic, with six million copies sold - Mamma Mia! sold an amazing three million in just one week.

11/12/2008 01:01:01