Our play opens in the mythical land of Arcadia—a place which Father Time has forgotten about and in which the inhabitants live a completely blameless life, are eternally young, and have never heard of "that impious thing" A LIE! (Any resemblance between this country and East Kilbride is, of course, purely co-incidental!) Into such an idyllic atmosphere is precipitated a certain James Smith—a London restaurant proprietor with a roving disposition (and an eye to match)—and he at once attempts to make the most of the situation by flirting with Sombra. He finally causes a sensation by telling a lie, and is forthwith immersed in the Well of Truth, from which he emerges a bright-eyed, youthful lad, dressed in the scanty costume of Arcadia. It is then decided that he—now re-christened Simplicitas—will return to London, accompanied by Sombra and Chrysaea, on a mission whose object is to teach the truth to the English (Scottish Nationalists are asked not to comment here, please !)

The second act finds us at Askwood Races, on the day of the running of the Corinthian Stakes, and there we meet the popular young race-horse owner Jack Meadows and his friend Bobby. At short notice the only one available to ride Jack's horse - The Deuce - is that "merry-and-bright-and-also-ran" jockey, Peter Doody. Such misfortune might have meant more to Jack if he had not set eyes upon the charming Eileen Cavanagh, niece of James Smith. Jack has a rival in Sir George Paddock, a wealthy bookmaker, who, besides owning a fancied runner in the race, has high hopes of winning Eileen too, chiefly through the influence of Mrs. Smith, who is trying to wheedle money out of him for the Smith Catering business.

In the midst of a sudden thunderstorm (not unknown in England on a summer's afternoon) there appears the three visitors from Arcadia, and when once Smith realises that his wife does not recognise him he is not slow to exploit the situation to the full. There soon comes an opportunity for Simplicitas to distinguish himself. Peter Doody is unable to ride The Deuce and Sombra arranges that Simplicitas shall ride instead, first assuring the horse in Arcadian language that all is well.

Finally we are taken to Smith's Hotel, now known as The Arcadian Restaurant, the rage of London, where the diet is that of the simple life. Simplicitas, having somewhat forgotten the original purpose of his visit, is having the time of his life, but in endeavouring to explain the reason for an all-night absence, he tells a lie and is changed back to Mr. Smith. The Arcadians, Sombra and Chrysaea, decide that in trying to convert London to the truth they are attempting the impossible (we could have told them that some time back) and so they return to their native Arcadia.