Twilight Bar - An Escapade in Four Acts was first conceived (as Le Bar du soleil) and written in 1933, in last months of Koestler's stay in the U.S.S.R. The play was translated in Hungarian in order be represented at the Budapest City Theater, but it was later dropped. Koestler brought the manuscript with him to France, where he lost it during his flight and later internment in 1940. He re-wrote it in 1944 and published it in Great Britain in 1945.
The plot of the play is rather thin: in a country where a revolutionary movement is being crushed by the Police at sudden an extraterrestrial ship lands, letting out two "Investigators" that have to decide whether life on Earth is happy or not. If not, all human beings will be exterminated to make place for the inhabitants of the crowded extraterrestrial Federation. Earth has 48 hours to raise its Happiness Quotient to acceptable values.
The government of the country resigns, and "amateurs" take their place, starting the job of making everyone jolly. At the very last moment before the 48 hours term expires, the two "Investigators" are arrested because all the story is said to be a hoax, and the former Government returns in place.
In the play the theme of means and ends once more emerge (in the frame of the revolutionary struggle that is having place), but all the action rotates around the problem of ethics in politics (the "amateurs") and in life.
A funny thing to notice that, in the middle of all these themes, the "Investigators" state that, should the Happiness Quotient arrive to a satisfactory level, our planet will be spared, and another one (the next in the list) will be executed in its place. That is, a sort of "survival of the fittest" in enforced on a planetary level while the characters of the play discuss about "ends and means" and ethics, but only in the local scale.