I am a movie director and I just received the following movie plot. Could you help me answer this question? If not, let me know by writing "Not answerable". Plot title: I, Frankenstein Movie plot: In 1795, Dr. Victor Frankenstein (Aden Young) creates a monster (Aaron Eckhart), a soulless creature patched together from corpses, and then rejects it, disgusted with what he's made. In a fit of rage, the creature kills Victor's wife Elizabeth (Virginie Le Brun) and Victor chases it to the Arctic to get revenge, but succumbs to the weather. The creature buries his creator in the Frankenstein family crypt and is then attacked by demons before being rescued by the gargoyles Ophir (Mahesh Jadu) and Keziah (Caitlin Stasey), who bring it before the gargoyle queen Leonore (Miranda Otto) and their commander Gideon (Jai Courtney). Leonore explains that they were created by the Archangel Michael to battle demons on Earth and protect humanity. They name the creature "Adam" and invite him to join them, but he declines and departs after being given heavy, baton-like weapons to protect him, as more demons will come after him. The weapons allow him to "descend" demons (destroying their bodies and trapping their souls in Hell) as they have the symbol of the Gargoyle Order carved on them. Throughout the centuries, Adam fends off the demons that pursue him. During a modern-day confrontation at a nightclub, a human police officer is killed. While Adam is summoned by the gargoyles once more, the demon Helek (Steve Mouzakis) reports that Adam is alive to his leader, the demon-prince Naberius (Bill Nighy), who is disguised as billionaire businessman Charles Wessex, and his right-hand man, Dekar (Kevin Grevioux). Wessex has employed scientists Terra Wade (Yvonne Strahovski) and Carl Avery (Nicholas Bell) to conduct experiments with reanimated corpses, and sends a group of demons led by his most formidable warrior, Zuriel (Socratis Otto), to attack the gargoyles' cathedral and capture Adam so he can unlock the secret to giving life. Before Leonore can punish Adam for the police officer's death, the cathedral is attacked and Adam convinces Ophir to release him. In the ensuing battle, a number of gargoyles, including Ophir and... My question: Why is Adam immune to possession?
He has grown his own soul.