In writing the screenplay, Brook remained close to Lonsdale's play but changed its timeframe from the early 1920s to the late Victorian era, when the concept would have been much more shocking.

Maria grows tired of waiting for Richard to make his feelings known and proposes that they spend a month together as man and wife in Scotland "on approval" to see how they fare.

At the end of three weeks, Maria tells Richard that she is willing to marry him and even to settle £5,000 per year on him, but when he discovers that what he had thought was a test of his patience is actually the way in which she behaves normally, he rejects her.

Helen has long felt sympathy, but begins to feel an attraction toward Richard and suggests that they leave Maria and George alone together in the otherwise deserted house.

On Approval is one of few films featuring Lillie, often called "The Funniest Woman in the World" for her eccentric personality and portrayals in many comedic stage plays and revues.

[2] Observing that On Approval “is more like the work of human beings than you usually get today in films,” critic Manny Farber wrote in The Nation: This drawing-room farce about Victorians manages by amiability and a talented light touch to make its people and their half-assed lives quite lovable…The film doesn’t have the slightest look of modern movie design, which is a good thing.

It is thoroughly secure in its kidding, indifferent as to whether or not it is killing its audience—which it isn’t—and shows an awareness of the possibilities for achieving humor by a precocious use of the medium.

[3]Filmmaker Lindsay Anderson called the film "the funniest British light comedy ever made" (according to the DVD box).