Twins feature in other Shakespeare plays too, but only "The Comedy of Errors" has two pairs. To add to the confusion, the twins have identical names too. The plot revolves around the twins (both sets) being separated at birth. Antipholus and his servant Dromio have both grown up in Syracuse with Antipholus' father, Aegon. They know they have missing brothers and (in the case of Antipholus) a missing mother, and go in search of them when they grow up. In fact the other Antipholus, Dromio and their mother are all in Ephesus. Antipholus ii is now the richest man there, and Dromio ii is his servant. Confusion and mistaken identity form the comlex, fast-moving plot of the play. Eventually all are reunited and all is explained –everything is complete when the Abbess of Ephesus turns out to be Aemelia, lost wife of Aegon and mother of the two Antipholi.
The basic plot is taken from a Roman comedy, Plautus' "The Twins," but adding a second set of twins was Shakespeare's own idea.