film summary
Humourous escapades abound in the Invisible Woman starring John Barrymore in another classic performance as only he can give. Here, Barrymore is the slightly senile Professor Gibbs who has invented a formula to make people invisible. Virginia Bruce is working for a man she detests and decides to test the professor's formula when he puts an add in the newspaper, so she can give her boss a kick in the pants. Laughs proliferate when some gangsters also want the formula so their boss can get back into the country from Mexico. If you are looking for something in the Invisible Man trade, then try the Invisible Woman and you won't be disappointed.
Not everyone is motivated by money; Kitty Carroll, after one too many hard days in the garment district, was motivated by revenge. An appointment was made, and Kitty reported to the Professor's laboratory.

At first, the grizzled old scientist was concerned about the, er, personal details: "I expected a man," he finally said gruffly, "but you'll do." Of course, this being 1940, his housekeeper, Mrs Jackson, was pressed into temporary (and reluctant) service as chaperone, while Kitty disrobed behind a screen and the Professor administered some mysterious injection. Then an apparatus worthy of Dr Frankenstein was cranked up, and gradually the shadow of a woman faded into an empty space.

"She's gone!" The experiment was a success, and the Professor set off to inform Richard — but Kitty had better things to do. Muttering something about "Growley", she took off for points unknown. The Professor came back with Richard, but his Invisible Woman had, er, disappeared.
Back at the workplace, the invisible Kitty followed through on her plan, frightening snooty buyers and, more important, scaring the meanness out of management. Mr. Growley would never be the same again, and Kitty's fellow models would never know just how this change of heart came to pass.

Richard, mostly prodded by his manservant George, decided that the Professor had finally gone mad. Meanwhile, more sinister figures had seen the Professor's advertisement. The notorious Blackie, out of reach of the law, dispatched his henchpersons to find the Professor and swipe his process, so he could return home unnoticed. The thugs and Kitty arrived at the laboratory at the same time, and when the slickest of the thugs, a fellow named "Foghorn", posed as a "fellow scientist" to win the Professor's confidence, Kitty was happy to expose the fraud. Shortly thereafter, Kitty finally returned to visibility, and the Professor implored her to undergo the process one more time, so as to persuade Richard that it really worked. Not that Richard was going to wait around to be persuaded; he decided to go on an impromptu fishing trip rather than listen to the Professor again.
But the Professor wasn't about to give up. He and Kitty arrived at Richard's cabin by the lake; she disrobed, and they waited. Meanwhile, the cold and damp gave way to cold and rainy, and it occurred to the Professor that maybe they shouldn't have left Kitty's clothes outside. And as he hung up the garments on a makeshift clothesline — and as Kitty, unclad and freezing, kept sneaking drinks — Richard returned, and was startled by what he didn't see, though he was sure it wasn't worth seeing: "Any girl who'd become invisible can't be very easy on the eyes." Kitty, miffed, demanded to be returned to visibility, but the formula hadn't worn off yet, and wouldn't, said the Professor, until morning.

Having made his, um, presentation, the Professor retired for the night, and Richard and Kitty were left to snipe at each other. Finally wearying of his tauntings, she decided to show him a thing or two, so to speak, and donned the one item of clothing that wasn't still wet — a pair of stockings. Richard was, to say the least, taken aback.
"Does the rest of you follow this same interesting pattern?" he asked.
"None of your business," she snapped.
The next day, Kitty was still invisible, and the Professor, unable to explain why, suggested they return to the lab, where they discovered Mrs Jackson stuck in a closet and the invisibility apparatus stolen. The Professor found the situation somewhat amusing: they hadn't taken the injectable reagent, so the thieves couldn't possibly get it to work. Kitty, however, was disconsolate, and Richard was getting more anxious to see the rest of the poor girl. What had been keeping her invisible all this time? The Professor theorized that it was the effects of all the drinks at the lodge; he gave her a shot to counteract the booze, a new dress in which to make an appearance, and some words of warning: "No alcohol of any kind. When you dissipate, you disappear."

And that might have been the end of it, except for a minor problem at Blackie's compound in Mexico. Foghorn (remember him?) underwent the treatment as a test, and wound up not only still visible, but with a quavering falsetto instead of his usual basso profundo. Blackie, reasoning that the machine by itself wasn't enough to make him invisible, ordered that the Professor be brought to him at once. Thugs were dispatched, and the Professor and Kitty were abducted.
Meanwhile, chez Russell, George reluctantly opened the door, and a vaguely-familiar figure stepped through. "I can tell you where they took the girl and the Professor." It was the newly-vengeful (and still mezzo-soprano) Foghorn, blowing the whistle on his old boss. And the three of them headed down to Mexico to rescue the captives.

At Blackie's hideaway, the Professor, having declined to cooperate, was tied to a chair, which didn't keep him from deluging Blackie with some pseudo-psychological analysis of his criminal career, when Kitty happened upon a bottle labeled "Pure Grain Alcohol", and took a swig. "That stuff will melt your bridgework!" exclaimed one of the thugs. Impossible, said Kitty, she didn't have any bridgework, and kept on drinking, and sure enough, she vanished.

Ducking behind the Professor's apparatus to get out of her dress (thank you, Hays Office), Kitty, emboldened by her invisibility and just slightly tipsy to boot, wrought unseen havoc on Blackie's gang, subduing them while they stared in disbelief. Things were very much under control when the rescue party arrived, but Kitty was having so much fun she decided to fight them too — "If he wants me, let him fight for me!"
And so finally, it was Foghorn, with voice and vengeance both in fine fettle, who dispatched Blackie, but what Richard wanted to know, of course, was what happened to Kitty? The cry came from the balcony: "No, no, anything but that!" Then suddenly, a loud SPLASH! in the pool, and Richard dived in to rescue her from what surely must have been a fate worse than death, and everyone knew it was True Love.

Jump ahead at least a year or so. Richard and Kitty's baby is on the changing table, and everyone, even the Professor, is ooh-ing and aah-ing, when suddenly the baby fades away into nothingness. Perplexity rules, until the Professor spies a bottle on the side of the table: rubbing alcohol. "Hereditary," he pronounces, and our story is ended — for now.