Her name was Dora Jane Hamblin. She died in 1993, in a retirement home in Rome, at the age of 73.
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Two esteemed visitors to the set during shooting were Gloria Swanson and the film historian Kevin Brownlow. Kevin wrote about his experience that day, which David Robinson included in his magnificent biography of Chaplin.
Sadly, this was Chaplin's final film.
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But, right now, let's listen to Dora Jane Hamblin. These are excerpts of her article. The "Sydney" she refers to here is Charlie's son.
"Walking onto Charlie Chaplin's set at England's Pinewood Studios feels quite a bit like trying to tip-toe into church after the service has started. There are, to be sure, a lot of slamming doors and exploding champagne bottles and actors leaping around like scalded cats, but between the bangs and the crashes there is a silence quite unlike the perfunctory quiet of the ordinary movie set. Everybody's watching Charlie teach some new tricks to a trio of old pros - Sophia, Marlon and Sydney Chaplin. The stars sit rapt, like well brought-up children, hanging on his every word. That is much easier than hanging onto him.
"Marlon is supposed to chase Sophia around the furniture? Charlie takes off in a frantic deadpan dash, to show Marlon how he wants him to do it. Sophia is supposed to flee? Charlie skitters around uttering little yelps of alarm and casting arch looks back over his tweedy shoulder. Sydney Chaplin is supposed to puff on a cigar and make himself sick? Charlie Chaplin wraps his small hand around an imaginary cigar, tilts his head, and everybody not he set can smell the nonexistent smoke.....
"The new picture, though it is the 81st of Chaplin's 52-year movie career, is a first in a couple of significant categories: it is Chaplin's first film in color; it is the first time he hasher directed established stars, let alone a pair of Oscar winners and staggering personalities like Loren and Brando; and it is the first time in years that he has worked for a company not his own. Universal is bankrolling this one at an estimated production cost of $4 million and will distribute it. But Chapin is clearly running it. .... Hardly a day passes that Charlie doesn't mutter 'We're using too much film.' Actually, Charlie's first feature-length film, the six-reeler Tillie's Punctured Romance in 1914, had almost exactly the same shooting time as this present film, 14 weeks.
"'That was very, very difficult, that scene,' Sophia says. 'It was a charlie Chapin scene, you see. Silent, and subtle. He has the timing exactly right when he does it. Charlie never does the obvious thing, like most actors. He turns it all upside down, thinks of the opposite from the obvious thing.' "...
"'In the next few days I thought I had gone raving mad, Charlie had gone raving mad, and it was impossible,' says Brando. 'I can't do fades and triple-takes and things like that, and I was wanting to go to Charlie to say, 'I'm afraid we've both made a horrible mistake. But then it all started to work out. With Charlie it's chess, it's chess at 90 mph.' ...
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"'Well, that's my contribution,' he said as he walked off the set. Kona gave him a big kiss and everybody told him the scene was wonderful. The only reason there wasn't a round of applause was that everyone in the place was afraid he might snap at them. 'Quiet, now let's all be adult!'"
And so ends the article. I've included photos from the magazine, which were shot by famed photographer Alfred Eisenstaedt.
Also included is an ad from that same issue which features another very funny man.