'Game of Thrones' and the Chilling Science of Bringing People Back From the Dead

When Jon Snow, Lord Commander of the Night's Watch on HBO's Game of Thrones, was slain at the hands of his brothers-in-arms at the end of season five, it looked like the end of actor Kit Harington's role as a haircut we'd look forward to every week. 

From the moment of Snow's death, however, the GoT fandom was convinced he'd come back. And finally, two episodes later, the red priestess Melisandre — vaginal birther of smoke demons and supercentenarian in disguise — mumbled some High Valyrian and brought Jon Snow back from the dead. We rejoiced. And then we wondered, "What the hell?" 

In the supergeek tradition of applying real-life science to TV show magic, we sought to find out: Could Melisandre, or anyone, reanimate a body without spells?

First, let's recap the last few episodes

Jon Snow, supposed bastard son of slain hero Ned Stark, was the leader of the Night's Watch, a group comprised largely of reformed criminals and ruffians who protect Westeros from threats in the north, including the lawless wildlings; frozen, zombie-like wights; and icy, humanoid entities known as White Walkers. When Snow made peace with the wildlings, some of his men rebelled and conspired to kill Snow; the final blow was delivered by his preteen steward. (Looking at you, Olly, you fucking Judas.)

In season six, those loyal to Snow discover their commander's body and bring him inside. An episode later, Davos Seaworth asks Melisandre to come resurrect Snow. During this time, Snow shows no signs of decay — meaning either very little time has passed or it's so cold his body isn't able to decompose. This is crucial; more on that later.

Doctors use real science to bring living beings back to life

"We've all been brought up to think death is an absolute moment — when you die, you can't come back," Sam Parnia, an assistant professor of critical care medicine at Stony Brook Medicine, told the BBC. "It used to be correct, but now with the basic discovery of CPR, we've come to understand that the cells inside your body don't become irreversibly 'dead' for hours after you've 'died' ... Even after you've become a cadaver, you're still retrievable."

In the words of the Ironborn, what is dead may never die — as long as the cells are still viable.

In George R.R. Martin's world, red priests seem to be able to restore life in any condition, regardless of climate; but in our world, those cadavers have to be cold as shit.

Castle Black, where Jon lies, is extremely cold. Enough to keep a gigantic wall of ice frozen solid in perpetuity. Keeping human tissue cold, even freezing, is often critical for life-saving surgery. 

In 2014, Dr. Samuel Tisherman, with a team at UPMC Presbyterian Hospital in Pennsylvania, started trials for keeping gunshot victims alive by chilling them and replacing their blood with a chemical coolant. The scientific term for this process is emergency preservation and resuscitation, or EPR. Others call it suspended animation. Whatever you call it, it gives surgeons more time to operate without worrying about blood loss.

Tisherman's team inflicted sedated pigs with near-fatal injuries, representing gunshot or stab wounds. The pigs in the experiment no longer had a pulse, and most of them had already lost half their blood.

A tube was put into the pigs' aorta, which was used to pump coolant in and blood out — draining them like a victim on Dexter until the body was at about 50 degrees Fahrenheit, less than half of the pigs' normal body temperature. After surgery, the solution was replaced with the pigs' old blood.

Nearly 90% of the pigs recovered once they got their blood back.

The interesting part: The blood isn't necessary to keep cells alive if the body's metabolism stops. (That's good news for Jon Snow, since he doesn't have a lot of blood left.)

Based on where Snow was stabbed, it looks like mostly organ damage in the abdominals, with a weird, moon-shaped slice in his sternum. The blades may have missed his heart.

So now the body's back. What about the brain?

So now we have a body, surgically fixed while practically frozen. That still leaves the brain and all the moving parts that keep your brain connected to your body. It's true that when you're in a state of cold-induced suspended animation, your body's metabolism drops to prevent brain damage from oxygen starvation.

But what if the time Snow spent being dead led to cognitive problems? What if he were brain-dead?

A life sciences company called Bioquark thinks it has the solution: a program called the Reanima Project, which claims it can reverse the effects of brain death using neural regeneration and reanimation, similar to reptiles and and amphibians. "With amphibians, you can blow their brains apart, in some case remove them entirely, and the brain grows back," said Bioquark CEO Ira Pastor in a phone interview. "We're focusing on developing proteins and other biomolecules to recapitulate these dynamics in humans."

According to Pastor, a brain-dead body can still function and do a lot of lizard-brain tasks — the things you take for granted as a being of higher consciousness. So, in the case of Snow, if regular body function were returned (through blood magic, obviously), Pastor says it wouldn't be impossible to regain full cognition after the fact.

"If you lowered the body temperature to prevent brain death events, and were able to reinfuse blood to stop the major cascade of inflammation, we would not say that's far-fetched," he said, referring to the idea of bringing a person back to life. "We're starting with the brain stem, looking at independent breathing and heartbeat. But the goal at the end of the day would be to reintegrate the entire central nervous system."

You don't need magic to bring someone back to life.

Time is a major factor in the ability to reanimate a dead ("dead") person. In 1986, a drowned 2-year-old was brought back to life three hours after her time of death. A 17-year-old came to again after being dead 20 minutes from cardiac arrest. A 40-year-old was revived after three and a half hours of resuscitation. People have come back from being dead in weird ways.

In today's world, Melisandre wouldn't be a red priestess. Maybe she's just a surgeon from Pittsburgh with a tank of coolant and a few pigs.