…and other stories about the film’s classic invisible VFX.

Forrest Gump – which is celebrating its 25th anniversary this week – is full of memorable invisible effects by ILM. Who can forget the opening feather ‘oner’, the times Gump meets different US Presidents, and the jaw-dropping moments where Lieutenant Dan is seen with no legs.

Owing to significant coverage at the time of how these incredible shots were done, including a number of making-of featurettes, many may already be familiar with how ILM pulled those off.

But at a VFX conference earlier this year, two of the film’s visual effects crew, George Murphy and Stephen Rosenbaum (who, along with Ken Ralston and Allen Hall, received the Academy Award for Best Visual Effects for Forrest Gump), shared some stories about the Robert Zemeckis movie with me that I don’t think I’d heard before.

These included the moment ILM showed Gary Sinise the missing legs shots for the first time, the way the ping pong sequences were made, and a surreal experience the pair had on the Home Shopping Network after the film was released.

‘But you ain’t got no legs, Lieutenant Dan’

ILM digitally removed Gary Sinise’s legs for several shots in the film, after the character Lieutenant Dan’s injuries sustained in the Vietnam War. The actor wore blue stockings for some scenes to help with isolating the legs.

Then, in certain shots, set props would be rigged to allow for the shot, such as a bed having a section cut out of it for Sinise’s actual legs to go through.

“To take off his legs, it was all about background replacement and then tracking in 3D knee caps with bandages,” said Rosenbaum at SparkFX 2019 in Vancouver, where he and Murphy spoke about Forrest Gump. “It was pretty straightforward by today’s standards but it certainly shocked a lot of people, including Gary, actually.”

Indeed, Sinise would be one of the first to witness how ILM pulled off the trick, as Rosenbaum recalled. “In a trip down to LA, we were shooting the apartment scene, and we had just done the hospital bed shot, and we were waiting out the back at the set waiting for them to finish a set-up, and Gary came out. I’d never met him, so I’m standing there and he introduced himself and I told him who I was and what we were doing and that we had that shot with us. And he said, ‘I want to see it!’”

“So, suddenly it turned into all eyes being on this footage for the first time. And Gary flipped out, to see himself without legs was pretty shocking.”

Gump and ping pong

For scenes of Gump visiting China as a ping pong champion, actor Tom Hanks and his opponent mimed playing table tennis in the principal photography, aided by a metronome for timing.

The final shots by ILM would involve extending crowds as well as adding in the ping pong ball itself, complete with appropriate motion blur.

“People are not going to believe that all we had was a high resolution single frame photo of a ping pong ball and it was tracked into the scene,” said Rosenbaum.

“The thing is, ILM had amazing animators who had come from the optical days,” noted Murphy. “So they came in and we said what we wanted was to make it look like a real pong pong ball, bouncing, arcing and slicing, and they just knew how to do this.”

So, where’s that ping pong ball that ILM used for reference right now? “There were several,” said Murphy, who admitted that he “might have one of those ping pong balls in storage somewhere.”

Through the Eyes of…Stephen and George

After the huge success of Forrest Gump in cinemas, there was a home video release of a ‘making of’ of the film (called Through the Eyes of Forrest Gump, directed by Peyton Reed, the director of the Ant-Man films). In an event that is unlikely to have ever occurred since, Murphy and Rosenbaum were enlisted to help sell that Gump making of video on the Home Shopping Network.

“Nobody else stepped forward and apparently we were volunteered to go out to Pennsylvania to go on the Home Shopping Network to do a half-hour segment on Forrest Gump,” said Murphy. “The interesting part of that was in the waiting room, while we were waiting to go on, where the woman who had invented the Miracle Mop was sitting next to us.”

“It’s this live TV show with hundreds of calls coming in,” added a bemused Murphy. “Just the sheer amount of money that was being made per minute was a real education.”