Bill Hader's Richie Tozier is undoubtedly one of the best parts of "It: Chapter Two." The character, who was played by Finn Wolfhard in the first film and grew up to be a comedian in the sequel, brings a relatable sense of humor to some genuinely horrific scenarios. His fear also feels very real, which makes sense, because apparently one of Pennywise actor Bill Skarsgård's special skills deeply spooked Hader.

Skarsgård and series director Andy Muschietti have gone on the record before about Skarsgård's impressive physical transformation into Pennywise. In an interview for Entertainment Tonight, they talk about how Skarsgård can arrange his expressions in a terrifying way without CGI. He's able to curl his lip in an unnerving way, and can also make his eyes cross and uncross, giving the uncanny appearance that they're working independently of one another.

Pennywise's Wandering Eye

It's that last talent that apparently sent Hader running for the hills when he first found out about it. Per Vulture, Hader appeared on "Conan" during the film's press tour to talk about hilarious set photos that went viral during the filming of "It: Chapter Two." In the pictures, Hader is speaking with Skarsgård, who is decked out in full clown makeup and costume. The two seem to be sharing a laugh, but in the next photos, Hader looks startled, and actually begins to run away from the actor.

According to Hader, Skaarsgard can be really scary when cameras are rolling, but it was specifically that eyeball trick that really freaked him out. "I go, how do they do that thing in the first movie, where your eye kinda goes out?" the comedian said. "I go, 'Is that a digital thing?' And he goes, 'Oh, you mean this?' And he did it!" Hader then impersonated his reaction, which can be best described as a disturbed scream.

If Hader got up close and personal with Skarsgård's wandering eyes during shooting, it's tough to spot in the final cut of "It: Chapter Two." In a scene in the Derry park, the monster taunts Richie about a childhood secret, but when his eyes start to cross, his whole face also seems to melt in a shot that's clearly CGI. Presumably, the actor was doing the eye trick in real life, but the look was enhanced after the fact for maximum freakiness. This scene matches up with the now-memed photos of Hader running from Skarsgård, so it's a safe bet it's the one that had the actor rattled.

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The post The IT Chapter Two Scene That Terrified Bill Hader appeared first on /Film.