“The Man with the Invincible Gun” is one of Nolan’s sci-fi novels that he asks Mark to take a closer look at while he’s being taken away by the Viltrumites.
Warning: This article contains heavy spoilers
Nolan wrote a collection of sci-fi books during his time on Earth, the distribution of which was handled by Cecil with the proceeds supporting Nolan’s family.
Even after Nolan’s true colors are revealed and he leaves the planet, Debbie continues to receive the money from the books until she decides that she doesn’t want Cecil to hold something over her anymore.
What Nolan doesn’t reveal is that the books are based on his actual adventures across the galaxy, which is why he specifically mentions them to Mark while he’s being taken away.
A rare weakness
Nolan’s book is actually referring to an alien known as the Space Racer, who he called the “Space Rider” to conceal his true identity. The Space Racer possesses a gun that can fire invulnerable blasts and can only be fired by him.
The blasts are one of the few things in the galaxy that are lethal to Viltrumites. Nolan defeated Space Racer and separated him from his weapon so that he wouldn’t be able to retaliate.
This character appears in the comics and eventually joins forces with Mark and Allen against the Viltrumites.
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