The plot concerns the interrelations of theater people before and after a first-night tryout, when they experience nervous anticipation, perceived failure, and unexpected success in sequence.

[1] There are allusions to figures from the larger world of New York shows, including David Belasco and George Jean Nathan, as well as topical references to the late 1940s stage scene.

The most egregious of these was Hart's mention of real drama critics[fn 1] then active in Boston, attributing to them spurious quotes for the fictional tryout.

One or two at a time the other characters come in and are introduced: Carleton FitzGerald, the overly emotional director; Frances Black, the shockingly outspoken wife of the producer; Owen Turner, the experienced older playwright just stopping by for a drink; Stella Livingston, the star's pessimistic mother who prophisises doom; Peter Sloan, the starry-eyed young trucker turned author, whose novice effort is now being given a tryout; Sidney Black, the excited, over-eager producer sponsoring his first play; and finally, Irene Livingston, the self-absorbed, aristocratic-behaving star.

He has copies of the early morning papers, from which it is learned the audience were largely his drunken compatriots, with the critics hailing the play as very good but needing some work.

[2] The critic Cyrus Durgin proved a forthright reviewer,[fn 3] identifying a major flaw with the second and third acts, where the hilarity of the fast-paced opening is followed by long self-pitying diatribes from the young playwright, the abrupt change in mood confusing the audience.

[15] Calling the actors "runners in a comic steeplechase", Atkinson said "Under Mr. Hart's excitable direction the performance races around the stage like a volcanic circus, everybody shouting, everybody making exits and entrances and slamming doors".

John Chapman at the New York Daily News was nearly as enthusiastic about the play, calling it "a noisy and rollicking comedy about the art of drama".

[16] He also wrote a follow-up article on how Light Up the Sky paralleled the fictional play within it, in that the Boston critics had recommended changes to make it successful.

Originally named J.J. in suggestion of a certain theater-owning magnate,[1] a newspaper column reported, shortly after the premiere and without explanation, that it had been renamed to Orson.

[17] One dissident critic was George Jean Nathan, who wrote a plaintive column, more about his bruised ego than the play, which he described as "crude and pretty vulgar".

[19] During the last weeks of the production Moss Hart had declined his royalties as author and director so that the "angels" (stage lingo for sponsoring producers) could get their original investment back.

[21] Bernard Hart told reporters that the investors had made a profit of only $10,000, which led them to sell the national touring rights to another producer.

[22] This was perhaps a mistake, for by the time the tour opened in Wilmington, Delaware on October 7, 1949[23] the East Coast had been saturated with summer stock and community theater productions of the play.

Sam Levene, Glenn Anders, Barry Nelson, Audrey Christie, and Phyllis Povah all reprised their parts,[26] but Virginia Field had already left town.