Aha! The long-lost princes appear in this act, as does the box of poisons (remember — not actually dangerous, just sleep inducing), and even hints of war appear at the edges. Plot lines start to cross, with complications ensuing.
In brief: Cymbeline, encouraged by his Queen and Cloten, refuses to pay the annual tribute to Rome first arranged by Julius Caesar. They’re quite welcoming to the Roman ambassador, General Lucius, and all but Cloten are polite in their refusal to pay. Then we see an unhappy Pisanio with a letter from Posthumus telling him to kill Imogen. He delivers another letter to Imogen in which Posthumus asks her to meet him in Wales, and she leaps at the chance. Next the two missing princes appear, just outside a Welsh cave where they’ve been raised by Belarius (long banished from Cymbeline’s court — he stole the babies as revenge). Although ignorant of their royal birth, they yearn for the lights and excitement of the big city, but Belarius temporarily satisfies them by saying, basically, “If you knew what I know, you wouldn’t be so eager to leave this calm and restful cave.”
Belarius and the princes head off to catch dinner just as Imogen and Pisanio appear. When Pisanio reveals Posthumus’ desire for her death, Imogen doubts her husband’s fealty and begins to excoriate all men (in echo of her husband’s rant against women). It takes all his wiles for Pisanio, who believes his master innocent, to calm her and explain his plan: Imogen is to disguise herself as a young man and travel to Rome to learn the truth about her husband’s behavior. Pisanio must return to court, but he leaves the box of poisons (he thinks they’re medicinal potions) with Imogen, in case she feels ill.
The three hunters return with a deer and discover her (already disguised) inside their cave — “I’ll love him as my brother,” says one of the princes; Imogen, in an aside, wishes these men had been her father’s sons.
Situational irony, anyone?
Back at Cymbeline’s court, Cloten hatches a plot to kill Posthumus (whom he believes is in Wales with Imogen) and rape her. Oh, and in Gaul, General Lucius is gathering forces to attack Britain.
The disguises (a common Shakespearean plot device) promise confusion, so I predict Cloten will be nearly killed by someone who mistakes him for Posthumus, and Imogen may find herself thrown into battle against the invading Roman army.
Side notes: In Scene i, reference is made to Julius Caesar, “whose remembrance yet/Lives in men’s eyes and will to ears and tongues/Be theme and hearing ever”. I can imagine above the Globe during this performance would be flying a black flag, advertising a performance of Shakespeare’s tragedy, Julius Caesar, on the following day.
And Calmgrove will be pleased to read “I have not slept one wink” (Pisanio to Imogen in scene iv) and “The game is up” (Belarius’s soliloquy at the end of scene iii) come from this act. However, connecting “wink” with sleep doesn’t originate with Shakespeare; it’s found three centuries earlier, in Robert Mannyng’s Handlyng Synne (1303): “Ne mete ete, ne drank drynke, Ne slepte onely a-lepy wynke.”