Abraham Sapien, born Langdon Everett Caul, is a fictional character in the comic book series Hellboy, created by Mike Mignola.

Believing him to be Oannes reborn, the society sealed the developing icthyo sapien's body in a tube of water in the hidden laboratory beneath a Washington, D.C. hospital until such time as he was fully formed.

With no memory of his life before, the icthyo sapien received a new name from a piece of paper attached to the tube, dated the day of Abraham Lincoln's assassination (April 14, 1865).

Cavendish was a contemporary of Langdon Caul, who killed the mad monk Rasputin, foiling his plans to unleash the Ogdru Jahad to destroy the world.

Aware of the imminent apocalypse, the society was determined to save at least some of mankind's spiritual essence, and were poised to use bombs to cause massive tidal waves which would devastate the southern hemisphere.

The Flame revealed that Abe was going to be the epicenter of this new Earth and that he was a fully evolved version of the frog monsters: one of the New Men first mentioned in Hellboy: Conqueror Worm by Rasputin.

According to Professor O'Donnell, Fénix is equal to the ancient Hyperborean shamans who keep the Ogdru Hem for entering in Earth after Hyperborea's fall using the Vril energy.

In Monsters, it is revealed that Abe's condition in the BPRD headquarters suddenly worsened, and, despite putting him on life support to keep his body alive, he suffered extensive brain damage.

Kate Corrigan, highly desiring her friend's return, sends agents to bring him home but eventually give in due to more pressing matters.

In the Abe Sapien series, Abe traveled through the US on a quest to prove he was not part of the apocalypse and avoid the BPRD (fearing death and dissection from Devon's influence), first travelling to the Salton Sea to inspect the Ogdru Hem there, then back to Texas where he was shot and finally to the undersea temple where Langdon Caul found the relic that transformed him.

Abe although was not the only one looking into his origin, Gustav Strobl was magically weakened due to the turmoil in hell caused by Hellboy and became desperate and disillusioned by the fact it was nearly the end of everything and he didn't have significant part to play.

Abe was psychically contacted by Shonchin, who revealed that the jellyfish entity was an ancient hyperborean shaman of the right hand, who transcended to that form after being martyred by worshipers of the black goddess.

After Hellboy killed Rasputin at the cost of his own life, his and Hecate's spirits called upon Liz to cleanse the damaged Earth of the Ogdru Jahad's corruption, releasing her full power, reducing the earths surface to a smoking cinder so Hellboy could enter Hecate (as an iron maiden) and his blood remade the world anew.

Sapien appeared in the film's 2008 sequel, Hellboy II: The Golden Army, in which he was played by Doug Jones who provides his speaking parts.

This version of the character, although similar to the movie Sapien, is much more like his comic book counterpart, showing signs of neither the psychic abilities nor breathing apparatus.