As the fifth season premiere of Game of Thrones inched towards its Sunday debut, we wondered whether HBO could withstand so many fans rushing its Internet doors. Major GoT airings have made the HBO Go service falter in the past, and this time, the company's spanking-new HBO Now offering would have to withstand a whole slew of "Thronies."

As it turns out, HBO's servers held up just fine, but something else sprung a leak. Before the fifth season's first episode officially aired in the United States, it had already leaked online—along with a few more episodes. The season's first four episodes appeared on torrent sites late Saturday night, and they all appeared to have been sourced from DVD "screener" copies that had been sent to critics ahead of the season premiere.

We're used to TV episodes popping up on torrent sites as soon as they air; it doesn't take much more than a capture card, a modern PC, and a decent broadband connection to nab some sweet Internet notoriety. But we were dumbstruck by the mess HBO found itself in. It's 2015. What the heck were they doing?

Ironclad stuff?

These days, many films, TV series, and albums don't leak before their release date and sometimes they stay hidden until the last second possible. Case in point: Beyoncé managed to record an entire album—and film a music video for every song—without the world knowing until it launched as an online purchase at the end of 2013.

Queen Bey pulled it off by doing what pretty much every other media company does these days: blanket projects in code names and non-disclosure agreements, and take extra care not to send key files through unprotected online channels. Sometimes, of course, the latter half of the equation gets bungled, as Madonna learned late last year when an Israeli man illegally accessed unfinished song mixes from an upcoming album of hers.

Plenty of people who schlep in Hollywood's industrial trenches—your production crews, your caterers, your set designers, your costumers—sign non-disclosure agreements when they work on a TV series or film, which includes bans on smartphone use and social media on set. That's typically more to control the image of a series and its actors, not to mention reduce any chances that fans learn about spoilers or filming delays; we don't ever expect to see a boom mic operator film, edit, and upload an entire episode of The Walking Dead that he recorded on his Nexus 5 when he thought nobody was looking.

Still, it's the kind of ironclad stuff that you hear about and then wonder how the heck four episodes of a series could leak in the bat of an eye.

“That doesn't prove you robbed the bank”

HBO has yet to publicly confirm that GoT's leak originated from a DVD screener. Currently, HBO spokespeople have made the same statement to multiple outlets, including Ars Technica: that four episodes had leaked, and they "originated from within a group approved by HBO to receive them." (HBO declined to answer any of our other questions about the Game of Thrones leak and how the company handles preview access to its content.)

We checked the leaked-episode files to confirm their 720x392 resolution, which is in line with a DVD rip—and not indicative of any further cropping the screen to hide, say, any hidden watermarks on the screen's edges—and we confirmed that the leaked episodes contained a blurred watermark at the bottom-left of the screen at all times.

Managing and producing individual watermarks on a series of DVDs is a much larger undertaking than doing so digitally—but more importantly, a name can't be assigned to a leak simply because a DVD watermark appears. As one expert said to NPR all the way back in 2006, if "your car is found by police at the scene of a bank heist, that doesn't prove you robbed the bank." When a leak is sourced from an online stream, however, there's much more identifying information—a confirmed log-in, a potential timestamp on the source video, and so on.

Thus, we were surprised that HBO chose to send DVDs to members of the press, since the network already has a system in place to manage digital preview distribution of its content. That's not just in the form of the ready-to-consume preview content that is publicly teased at HBO's Screening Room site. We know that in some cases, HBO has sent unfinished versions of episodes to the press through a digital distribution system hosted by Pix System, including ones with incomplete sound and visible green screens. (We reached out to Pix System to ask whether it was involved with HBO's Game of Thrones preview program, and we will update this report with any response.)

Typically, these kinds of digital preview systems require log-ins that only work within a limited time window, and they smother whatever you're watching in at least one giant, obvious watermark of a viewer's name and associated organization—the kind that would be too big to not fully obscure, which would help any HBO investigator figure out the source, as opposed to the itty-bitty watermark that is visible (and blurred) on this week's GoT leaks.

While other watermarks may have been hidden in those GoT screener DVDs, hackers have gotten very good at recognizing things like whole frames of video with marks—and have been able to remove them from other screener DVDs. Newer online-streaming preview systems may be similarly easy to compromise, but for now, they have the lead because they don't offer obvious ways for users to disable their giant, screen-filling watermarks or find an unencoded source stream address in order to somehow grab clean images or video. (Questions to Netflix and ABC about their own digital preview interfaces, which include watermarks as described above, were not answered as of this article's publication.)

The major hanger-on to the old guard of preview distribution by way of DVD is awards season. For years, individual studios have chosen to mail "For Your Consideration" DVD screeners to members of the Academy and SAG-AFTRA members. The number of studios who do so is pretty staggering, as proven by one film critic's giant tally of screeners he received for the 2014-2015 season.

This didn't work out so well for Hollywood at the end of last year, thanks to pirates' successful efforts to defeat watermarks and flood torrent sites with a huge number of Oscar-nominated films, all sourced from DVD screeners. We imagine that major studios may finally change their tune in light of films like The Hobbit: The Battle of Five Armies, Birdman, and Selma leaking before this year's Oscars ceremony, but they have not made any statements to indicate a shift in strategy. We wonder whether the issue has to do with critics refusing to use computers to access preview content in favor of comfortable home-theater setups, and we posed that question to a SAG-AFTRA representative.

"We have not heard of any changes to current [preview access] plans for the upcoming [awards] season," SAG-AFTRA publicity executive Rosalind Jarrett Sepulveda said to Ars. "It is, of course, important that our nominating committees to have the opportunity to see potential nominees' work and for our wider membership to see the nominated performances. We work closely with the studios and networks to make their films and TV shows available to our members."

But the DVD screener's days are probably numbered. Pirates may find ways to defeat digital preview systems, as well, but DVDs have already been proven utterly defeated. Critics may be infuriated by having to, say, attach their laptops to their home theaters via HDMI cables, but perhaps HBO, and the rest of the Hollywood publicity world, would be best tossing that old video-preview world into a canoe, pushing it into the sea, and setting it on fire with an arrow cast from afar.