How do you promote the most popular TV show in history? Do you even need to?

While HBO was preparing to say goodbye to its biggest draw, they also had several spin-offs in the works. We needed to prove that Game of Thrones doesn’t die with the show’s finale—it could be as enduring a franchise as The Lord of the Rings.

In addition to our initial objective of building anticipation and viewership of the premiere, we also defined an entirely new objective altogether: to transform a single show into an enduring franchise and cement its legacy for years to come.

When extreme winter weather caused an emergency blood shortage for the American Red Cross, a show known for its bloodshed rallied the world’s most diehard fans to prove their devotion to the show–by bleeding for it.

Anyone who donated blood for the throne had the chance to win the ultimate prize—to watch the season eight premiere ahead of the worldwide release.

“Bleed for the Throne” kicked off with an immersive experience at SXSW, before rolling out nationwide and spreading across the world.

Game of Thrones is no mere book or show—it’s become an entire cultural world, filled with creativity and fueled by unparalleled fandom and devotion.

To communicate this, we wanted to demonstrate the lengths the world—from fans to brands—would go #ForTheThrone.

While #ForTheThrone was designed as a campaign platform to promote the final season, we also wanted it to demonstrate GoT’s unique ability to inspire devotion for the good of humanity—for the betterment of the world.

And in the spirit of a show famous for its gory tendencies, what better way than to spill a little blood (the real kind)?

To get GoT’s army of fans fired up, we launched a film depicting the bloodiest sacrifices characters have made in the show, and then posed a simple question: “They’ve all bled for the throne, will you?”

We then followed up with something we knew they would do anything for–a chance to see the Game of Thrones season 8 premiere before the rest of the world, and it was game on.

We kicked off by creating an immersive experience at SXSW where festival-goers could walk in the bloody footsteps of different characters before making the ultimate sacrifice and bleeding for the throne themselves. After SXSW, over 3,000 blood drives were held nationally over a week before spreading to 17 other countries in need of blood donations.

In the face of a blood shortage caused by a weak US winter recruitment period, “Bleed for the Throne” gathered 13 times more blood than what was lost in the shortage.

352,344 people donated over the campaign period which equates to 349,660 usable units of blood.

Not only does this reflect an increase of donations by 12 percent versus the year prior; most heartening to us was that one out of every five donations came from new donors. In the end new donors grew 21 percent versus the year prior and contributed 61,519 units (for the throne), inspiring a new generation of blood donors for life.

It proves, to us at least, that Game of Thrones is no mere TV show—it’s a cultural franchise that has the ability to do something powerful for the good of humanity.