“Until “Bad Grandpa,” Johnny’s Irving character had worked on the earlier Jackass films for only a few days out of the entire shoot, at most,” Gardner said. “The challenge with the latest film - beyond the overall continuity required for 60 shooting days, out of sequence- was the fact that Irving had to exist as a real person in the real world, under close scrutiny in all sorts of situations, and also carry a narrative story. The biggest concern was knowing that we might not have access to him for touch-ups sometime for hours while filming, and that people would be practically nose to nose with him and have to buy off on this 86-year-old man as the real thing.” Gardner added, “The words of Producer Derek Freda were always echoing in the back of my mind, ‘If the makeup doesn’t work, the movie doesn’t work.’”
Beyond the army of artists and technicians at Alterian manufacturing all of the makeup effects elements and 11 silicone prosthetics needed for each of the sixty shooting days, it took another three to four makeup effects artists approximately three hours the morning of each day of filming to get Mr. Knoxville into his old man prosthetics…
Knowing the close scrutiny the character would receive on this film, Alterian rebuilt the character from the ground up this time, starting with a new lifecast of actor Johnny Knoxville. "In an effort to alter Irving to look less recognizable as the Irving from 'Jackass 3D,' we went back to his look for 'Jackass Number Two,' just refined more," said Gardner, "with a flatter, receding hairline and dental veneers added to dull down his teeth."
Oddly enough, Irving was officially introduced in "Jackass Number Two" in 2006 in a skit entitled "Bad Grandpa." You can view it here: http://alterianinc.com/
“We were a bit cavalier about our lack of pre-production time though, having re-created the Irving character four or five times already over the last twelve years,” Gardner stated. “If you had told us back at the start of “Bad Grandpa” that the film would be under close scrutiny itself for Academy Awards consideration, I think we would have tried harder to do a final makeup and camera test prior to filming. As it was, we had one practice run, one test day." He added, “Basically, we hit the ground running and never looked back!”