Among the crowd participating to Rasputin‘s ritual in Hellboy, there’s an unmistakable figure wearing a gas mask, made a fan favorite by Guillermo Del Toro in the original movie. Portrayed by Ilko Iliev, Karl Ruprect Kroenen is one of the few Nazis who manage to escape from the site, hinting at a potential return. In the 2004 adaptation, the character was radically modified from his comicbook origins: portrayed by Ladislav Beran, he’s some sort of steampunk zombie ninja, a formidable foe who started his career in the opera and slowly became a masochist monster experimenting on himself, becoming Rasputin’s most loyal disciple and main enforcer and a fierce Nazi commander. The character was meant to appear again in Hellboy III, with a storyline that would have revealed a shared past with Johann Krauss. In the comics, he’s not a swordsman nor a dust-for-blood zombie, but rather a scientist. Let’s take a look.
Born in Munich, Germany, Karl Ruprect Kroenen was one of the most brilliant minds of his time, a scientist who mastered a variety of disciplines, spanning through engineering, medicine, biology, chemistry and physics; unfortunately, he was also completely deranged. A successful surgeon, he wasn’t satisfied with the science of his time, as his true goal was to achieve immortality for the human race. He believed that the answer to his research could have been found in occultism, so he joined the Thule Society 
in the 1920s, starting a series of gruesome experiments in which he tried to extend the life of his human patients with a mix of surgery, electric engineering and black magic, with the sole result of creating monsters. In 1930, the Society involved him in an experiment aimed to harness the mystic energy force known as Shakti, but it all went badly, and in the resulting explosion Kroenen was horribly burnt and disfigured: with his body in ruin and his lungs barely functioning, he was forced to wear a protective bodysuit and a gas mask for the rest of his life. His work knew an unprecedented fame when Adolf Hitler rose to power, as the Nazis soon came to share Kroenen’s obsession with occultism, immortality and the likes. He became friends with another “unorthodox scientist” like him, Herman von Klempt, and met many stimulating people while working for the Third Reich… but nobody as fascinating and charismatic as Grigori Rasputin, a Russian monk who seemed to hold the key to all the knowledge Kroenen had been chasing all his life. Kroenen came to live for Rasputin’s words, and became his faithful disciple, with his loyalty to the monk surpassing by far that to the Reich. When, in 1944, Rasputin obtained from Hitler green light for his Project Ragna Rok, Kroenen participated as the lead scientist, assisting his master any way he could, hoping to be part of the great future he had promised.
Kroenen had helped Rasputin in 1941 to gather all the mystic relics he needed to prepare the ritual, and in that occasion he had proven his loyalty to him by getting almost killed by the spy A.N. Sandhu, but finally everything was ready. In Scotland, though, the ritual was apparently a failure, with nothing happening after its completion: Rasputin still claimed that everything had gone according to the plan, and while everyone abandoned him, only three of his 
disciples stayed with him. Kroenen, Leopold Kurtz and Ilsa Haupstein remarked their faith in the master, and for this they were rewarded: Rasputin prophesied the end of the war and the defeat of the Third Reich, and sent his three followers to a secret base in Norway, where they were instructed to await for him. Once there, thanks to Kroenen’s and Kurtz’s scientific and mystic knowledge, they hibernated themselves, waiting for Rasputin to awake them in the new world. Decades passed, and eventually Kroenen, Kurtz and Haupstein were revived in 1994 by Roderick Zinco, a man they almost killed before he could say he had been sent by the master (it was Kroenen the one who insisted to let him speak before disposing of him, like Kurtz proposed). As Ilsa left the base to pursue her own path, Kroenen and Kurtz stayed behind, waiting for the master. In solitude and inactivity, Kroenen started working on some of his old projects, like fusing robotics with corpses to create what he called the Apocalypse Army, 666 undead soldiers (the number was purposefully symbolic) to be put at the service of the master for his return. He also convinced Zinco to go to South America and retrieve the head of his friend von Klempt, still preserved in his hidden lab. Kroenen managed to reanimate von Klempt, despite Kurtz reminded him that Rasputin didn’t see the other fit for being his disciple and had rejected him from Project Ragna Rok. Apparently, Kurtz was right, as Kroenen now faced the greatest challenge to his faith yet: Herman von Klempt, in fact, immediately tempted with seizing control of the Apocalypse Army for himself, conquering the world without any master to serve…
Karl Ruprect Kroenen is the epitome of the mad scientist, a genius in a number of disciplines who’s obsessed with “forbidden” researches and who performs a variety of gruesome human experiments for the sake of knowledge. Despite being a real butcher in his lab, he’s a meek and tranquil man, who doesn’t share the brutality and violent attitude of many of his colleagues, and who always tries the most peaceful solution first. His gentle and humble demeanor, however, doesn’t mean he has to be taken lightly: he’s a monster responsible for atrocious crimes against humanity, and he doesn’t have for people more consideration than for a lab rat. Also, the blind faith he has for his master, Rasputin, only adds religious fanaticism to his already deranged ethics…
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