HOLLYWOOD GIN...The game of the stars
Historic Card Games by David Parlett

One of the reasons why the history of Gin Rummy remains tantalizingly obscure is that it didn't really come into its own until the 1930s, for as late as the 1926 edition of Official Rules of Card Games it was still being recorded under its older title Poker Gin or Gin Poker. One circumstance that helped it was the Depression when more and more people had less and less to spend on going out and enjoying themselves and had to rediscover the art of amusing themselves at home. Gin was much simpler to learn than Contract Bridge and more congenial in the family circle than Poker.

But perhaps what really helped it on its way was its popularity with actors, stars, and the celebrity-seeking riff-raff of Broadway and Hollywood, and the consequent publicity the game attracted to itself. Hardly a film of that period fails to mention it somewhere, or at least get it on screen. Even Flora Robson as Elizabeth I and Errol Flynn as the Earl of Essex appear to be playing it - though, unfortunately, not mentioning it - in The Sea Hawk (1940). Dale Armstrong reports:

"On one occasion, in a desperate effort at rescue, the [Burbank Lakeside Country] club's House Committee was forced to persuade rotund comedian Oliver Hardy (of Laurel and Hardy fame) to stay out of the card room, where the Gin sharks had been eating him alive for months, to the tune of four figures a week."

Two features of the game made it attractive to those hanging about in the wings waiting for their cue, or in the studio waiting for the greens man to revive the pot plants. One was that it was very fast to play but could, if necessary be left off at a moment's notice and easily picked up again as soon as the players were free. The other was the introduction of an ingenious scoring device - the so-called "Hollywood Gin" variety - whereby you could (in effect) play three games simultaneously, or even an endless series of them.

To say that Gin became a craze of that period would be to put it almost literally. Here's an account of it from the pen of Damon Runyon, who wrote an enormous number of humorous short stories set in and around Broadway and involving just about the craziest characters ever created.

"The cards in Gin-Rummy run hot and cold the same as the dice in a crap game. It is by no means necessary to go to Harvard to learn to play Gin and in fact, a moron is apt to play it better than Einstein. If you get the tickets in Gin you are a genius, and if you do not get them you are a bum. When they do not come you can only sit and suffer and the aggravation of waiting on cards that never arrive will give you stomach ulcers in no time.
Nearly everybody in the United States of America plays Gin-Rummy. The little children in the street play it. Old broads play it. I understand there is a trained ape in the Bronx Zoo that plays it very nicely and I am not surprised, because I can teach any dumb animal to play Gin-Rummy if I can get it to hold ten cards."


Reference:
This article was copied from Historic Card Games by David Parlett
https://www.parlettgames.uk/histocs/ginrummy.html scroll to 6th section on that page