Like Telemachus, Stephen (alternatively Hamlet/Shakespeare/Telemachus) has been thrust from his home and into his quest, thus initiating the dynamic action of the drama; unlike Telemachus, Stephen is not consciously aware that the object of his quest is a father-figure.
As in Hamlet, the action commences as characters move among castle turrets, or their counterpart. Soon, as we shall see, thoughts of a ghost will preoccupy Stephen Dedalus, our broody prince.