Shell Shocked

New Line Cinema and Jim Henson’s Creature Shop, where those costumes for the socko hit movie “Teenage Mutant Ninja Turtles” were made, have been hush-hush about who’s actually inside those outfits. We’ve learned that they’re all Hong Kong actors, except one: 18-year-old martial-arts master Ernie Reyes Jr.--late of ABC’s “Sidekicks” series--inside Donatello (actor Corey Feldman provides the voice).

Son of Ernie Reyes Sr.--who’s choreographed martial-arts sequences for numerous pics--Ernie was just 6 when he first performed his martial-arts moves at Madison Square Garden. He went on to display those skills in such movies as “The Last Dragon” (1985) and “Red Sonja” (1985) and on various TV shows.

As for his stint as a turtle, his rep tells us, “He had a great time, even if it sometimes got to be 110 or 120 degrees inside that costume.”