This probably isn't the person who hacked HBO, but it is the first thing that comes up when you search stock photos for "hacker." (Photo: Sean Gallup/Getty Images)

What appeared, at first, to be a few leaked episodes of Ballers and Room 104 and a script from Game Of Thrones has now revealed itself to be one of the biggest hacks in recent Hollywood history. Yesterday, we reported that the hack, which includes video and audio files as well as internal documents—but not employee emails—may have been bigger than the much-ballyhooed Sony hack last year. A story in The Hollywood Reporter confirms that, saying that hackers exposed 1.5 terabytes of information—seven times what was leaked from Sony—in a coordinated cyberattack.As a result, HBO has hired Mandiant, the same cybersecurity firm Sony brought on to conduct a forensic investigation into its cyber attack. The FBI has also joined the effort.

“At 1.5 terabytes, it could be a whole block of TV, or worse, it could be emails, financial documents, employee or customer information,” Erik Rasmussen, an employee of cybersecurity firm Kroll, tells THR. And the hackers are now threatening to reveal what exactly they’ve taken a little bit at a time, sending an email to Variety saying it will “release the leak gradually every week” starting at “Sunday 12 GMT.” It’s not clear where exactly the information will be leaked to, though, given that the website where the unaired TV episodes were first posted has been down for the past couple of days.