While happy he no longer has to wear the prosthetics used, he delighted in how scary the costume was to little children.
Fiennes said that he "knew the look was working" when he made a young boy burst into floods of tears on set while dressed in full costume as He-Who-Must-Not-Be-Named.
"I passed by the script supervisor, [who] has a little boy who was on set, four or five years old," he said. "I passed by this little child and I just looked at this boy, he just burst into tears."
Judging by the reaction, Fiennes was delighted by the response he got.
The actor also revealed that he wore a garter belt beneath his Voldemort costume.
"The costume was just a lot of flowing silky stuff I kept tripping over. What happened was the tights used to work their way down, so I couldn't walk as elegantly as I would have liked as Voldemort," Fiennes said.
"So eventually I said would you mind cutting them off so I had a garter belt, so for most of Harry Potter underneath the robes I had a very nice garter belt."