One very practical consideration to hold in mind is that the one-act play has a shorter time in which to focus attention than the full-length play and so the indispensable preliminary exposition must be quickly disposed of and an urgent appeal to the emotional interest of the audience must be made at the beginning. As has been said, every artistic consideration that calls for singleness of impression in the short-story is of equal importance in determining the unified structure of the one-act play. For the reason that a one-act play is almost never given by itself, if for no other, its effect will be dissipated if plot, characterization, or atmosphere fails in unity.
The writer exercising himself in the art of play-making had best begin with the procedure common to many professional playwrights. This first step is the drawing up of a scenario, which is an outline showing the course of the story, identifying the characters, indicating the setting and atmosphere and explaining the nature of the play; that is, whether, for example, it is to be a fantasy like _The Pierrot of the Minute_, or a comedy of manners like _Wurzel-Flummery_.
Here for instance is such a scenario as might have been drawn up for _The Boy Will_:
THE BOY WILL (Historical fantasy) Scenario for a one-act play, by Robert Emmons Rogers
CHARACTERS (in order of their appearance)
MASTER GEORGE PEELE, player of the Admiral's Company. GILES, a plump and peevish old rogue, a tapster. ANNE HATHAWAY, at sixteen a slim girl, niece to Giles. WILL SHAKESPEARE, a sturdy, ruddy boy, Anne's playmate. MISTRESS SHAKESPEARE, a kindly faced woman of middle age, Will's mother.
Within the White Luces Inn on a late afternoon in spring, 1582. (Here a description of the interior would follow.)
Peele is eating and drinking at the inn, waited on by Anne Hathaway.
Anne, scolded by Giles for her slowness, is commended as comely and spirited by Peele.
Anne explains her delay in fetching ale by the fact that Mistress Shakespeare has been at the back door inquiring for Will who has been gone all day.
Giles explains Will to Peele as a young poacher.
Anne indignantly denies the charge and praises Will as the brightest boy in Stratford.
Giles accuses him of gawking at plays and predicts a bad end for the boy.