The long prep time was necessary because Perlman was in full "Hellboy" wardrobe and bright red makeup when the 6-year-old leukemia patient named Zachary arrived at Spectral Motion, a movie special-effects company in Glendale.
Zachary was brought to Spectral Motion by the Make-a-Wish organization.
The Hollywood Reporter said Perlman, 62, agreed to step back into the role he played in two "Hellboy" pictures in 2004 and 2008 to help make the visit extra special. Zachary even got a chance to undergo the makeup procedure as well.
Spectral Motion hosted another Make-a-Wish kid earlier this summer, showing him the animatronics technology used in "X-Men: The Last Stand" and "The Fantastic Four: Rise of the Silver Surfer."