The placement of those shipwrecked is key to the plot of the play. Where are the characters washed up and why does this help the plot of the story?
The action takes place entirely on the tropical island that is home to Prospero, Miranda, Ariel, and Caliban, and its duration is only a few hours. The reader learns that Prospero and Antonio are brothers, and that Prospero is the rightful Duke of Milan but that his brother usurped his kingdom and exiled Prospero and his daughter Miranda. Fortune saved the two from their rotting ship which had been set to drift, and brought them to the island where Prospero has been granted supernatural powers by the enemies of Antonio. It is clear that the play embraces both the natural and the supernatural world.
Not only does magic play an instrumental role in the play, the atmosphere of Prospero's Island is in itself magical.