Act II ends with Hermia waking up only to discover that she is alone in the forest. She is frightened, and her fear has two sources: (1) being abandoned in the forest and (2) having a nightmare. Since the play is entitled A Midsummer Night’s Dream, Hermia’s nightmare is a dream within a dream. So, the reader should not be so surprised that her dream is linked to the main plot.
In a brief soliloquy Hermia describes that in her dream a serpent was eating her heart while Lysander stood by watching and smiling (lines 155- 56). The serpent could symbolize the love potion or perhaps even Puck himself. In any event, Hermia’s dream symbolizes that her love is being eaten away. And, of course, Lysander smiles without stopping the serpent because he has changed. He is under the spell of the love potion. He no longer cares about Hermia.
Shakespeare thus depicts that fate sometimes interferes in the lives of mankind with negative and inexplicable results. People are often fickle. One day a man may like a girl with brunette hair, but the next day he prefers a blonde. The ancient Greeks explained such fickleness by depicting an immature god of love who wielded a bow and arrow that could change a person’s emotions. Shakespeare does the same by depicting a mischievous fairy who is wielding a love potion.