Take a look at all the drama set to unfold in Episode 8 of the new season on Game of Thrones. Courtesy HBO.

SPOILER ALERT. If you haven’t watched the latest Game of Thrones episode, stop reading now. Seriously, go away. These are not the words you’re looking for.

The “explosive” conclusion to this week’s Game of Thrones episode left us all wondering the same thing. Would it actually be possible for someone to crush a human skull using their bare hands?

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Yes. No. Maybe. That is the indisputable verdict of science.

Over at The Washington Post, Lenny Bernstein asked two researchers who have studied the strength of the human head for their opinions.

“It would be impossible for even the strongest human to break the skull through compressive forces, exerted by any means, in any portion of the skull,” said Tobias Mattei, a neurosurgeon who also happens to be an expert on the effectiveness of bike helmets.

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In the episode, Gregor Clegane made Oberyn Martell’s head explode by applying pressure to his eye sockets. Mattei rubbished that strategy.

“It would only lead to a leakage of a clear fluid between the warrior’s fingers,” he said. “No explosion would be seen. The eyes of the victim would be pushed backward some few inches. That’s it.”

The other researcher Bernstein asked, a biomedical engineer called Cynthia Bir, was also sceptical.

“Knee jerk response is that there is no way to get the head to ‘explode’ by applying pressure from the eyes,” Bir said. “You would need to create pressure inside the cranium ... Once the cranium is breached at the orifice where the eye nerves enter, this pressure would be greatly diminished.”

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Well, that’s comforting. Kind of. But it isn’t the end of the matter.

Last year, when the film Star Trek Into Darkness raised the same harrowing question, Slate found a study in the Journal of Neurosurgery: Pediatrics which suggested it would be possible to crush a human head.

Researchers in the study subjected skulls to a “compression test”, pushing down on them using a pneumatic air cylinder and a steel plate. “Catastrophic failure” was accomplished with 520 pounds of force (2,300 newtons).

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That’s a huge amount of force for any human to generate, but of course, Gregor Clegane is no ordinary human.

Neither is the actor who plays him. Hafthor Bjornsson, an Icelandic strongman, is officially the second-strongest man in the world. In other words, he’s an absolute beast.

Pedro Pascal, the man who portrays Oberyn, has told Entertainment Weekly what it was like to fight Bjornsson on set.

“It was really intense,” Pascal said. “Just flying around this six-foot-eight, 420 pound (190kg) guy, who literally had a sword that went from the ground to my chin.”

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The actor believes Oberyn got what he wanted from the fight with Clegane, even though he perished so gruesomely.

“Before he can end this man’s life, he needs a confession. He needs to hear it,” Pascal said. “He still hears the confession, you know? I don’t even need to go on after that, once it’s been said out loud. And the ecstasy of achieving that, even though it’s being achieved in the instance of my demise.”

In another interview, with Vulture, Pascal described the unusual training regimen he used to prepare for his character’s final scene.

“I’d go to practice on my own. I bought a curtain rod from Home Depot, and I had this empty apartment,” he said.

“So I had all this space to learn this one particular move of helicoptering the spear and getting it to make this whooshing noise. So I practised that in the empty apartment and whacked myself in the face quite a bit.”

We imagine many people whacked themselves in the face with an open palm after watching Oberyn’s death scene. It was just that shocking.

At least one group of fans was captured on video during the pivotal moment, as they viewed it at The Burlington Bar in Chicago.

You can watch the fans’ reactions below (language and disturbing content warning). We think you’ll identify with their agony.