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Six-year-old Zachary had expressed to Make-A-Wish his desire "to meet and become Hellboy." The boy is undergoing treatment for leukemia, The Hollywood Reporter has learned.

Enter Spectral Motion, the creature effects house that brought to life the many fantastical characters in Guillermo del Toro's Hellboy (2004) and Hellboy 2 (2008).

They in turn approached Perlman, who "loved the idea and donned the makeup once more," Spectral Motion said on its Facebook page.

Perlman then underwent the four-hour makeup application procedure it takes to become Hellboy and shocked a delighted Zachary -- who later got the opportunity to become a pint-sized Hellboy himself. More photos of the memorable encounter are posted on Facebook.

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The visit was the second time in the past three weeks Spectral Motion has opened its doors to Make-A-Wish children. Another fan, Caleb, got a firsthand look at the animatronics behind some of the studio's well-known creatures, which also have appeared in X-Men: The Last Stand and Fantastic Four: Rise of the Silver Surfer.