Demetrius

Demetrius enters A Midsummer Night's Dream already compromised. Before he speaks a single line, the audience learns from Helena in Act I, scene i that he "made love" to her and "won her soul," then abandoned her to pursue Hermia. This backstory immediately marks him as someone whose romantic commitments cannot be trusted. He is handsome enough to be desired by two women simultaneously, well-connected enough to have Egeus's institutional backing, and self-assured enough to believe Athenian law is entirely on his side—yet Shakespeare strips away any heroic gloss by making his very first actions in the play coercive. He enlists a father's legal authority to force a woman to marry him, which is a far cry from the earnest, if foolish, romantic devotion that characterises Lysander.

Demetrius is also the only one of the four lovers whose identity is not defined by a single fixed attachment before the action begins. Lysander loves Hermia consistently; Helena loves Demetrius obsessively; Hermia loves Lysander unwaveringly. Demetrius alone has already switched allegiances once by the time the play opens, which makes him structurally the most unstable lover—and therefore the perfect target for Oberon's magic.

Demetrius's motivation in Act I is straightforward: claim Hermia as a legal prize. He follows her and Lysander into the forest in Act II not out of passion but possessiveness, threatening Lysander with violence ("where is Lysander and fair Hermia?") and using the language of ownership rather than love.

His forest arc consists almost entirely of rejection and reversal. He cruelly rebuffs Helena in Act II, scene i—telling her that her presence makes him "sick" and warning he will abandon her in the woods where she might be harmed by wild beasts—before Oberon, witnessing Helena's distress, orders Puck to anoint Demetrius's eyes with the love-juice. Upon waking to Helena in Act III, Demetrius undergoes an instantaneous transformation, suddenly producing elaborate, almost parodic declarations of devotion. His arc ends not with growth but with enchantment: by Act IV, Oberon chooses to leave the spell in place, and Demetrius wakes with his new love apparently permanent. He explains to Theseus in Act IV, scene i that his earlier desire for Hermia now seems like a "sickness" he has recovered from—language that ironically echoes his own cruel words to Helena in Act II.

• Act I, scene i — Demetrius stands beside Egeus before Theseus, invoking patriarchal law to back his suit. His silence while Hermia pleads for her own choice speaks volumes about his regard for her autonomy.
• Act II, scene i — His confrontation with Helena in the forest is the moral nadir of his characterisation. Threatening to leave her to the mercy of wild animals and declaring her proximity makes him ill reaches a cruelty that no enchantment can fully retroactively excuse.
• Act III, scene ii — Newly enchanted, Demetrius wakes to Helena and immediately enters the comic rivalry with Lysander. The near-duel that Puck manipulates and foils crystallises how completely he has become a puppet of supernatural forces rather than a self-determining agent.
• Act IV, scene i — Discovered asleep with the other lovers by Theseus and Egeus, Demetrius publicly declares his love for Helena and provides the convenient solution that untangles the legal knot. His "recovery" speech is accepted at face value, though the audience knows the spell remains active.

Helena is the relationship that most defines Demetrius, as it frames both his worst and his enchanted-best behaviour. His pre-play abandonment of her and his forest cruelty establish real harm; the spell merely restores what he had already voluntarily destroyed. Whether the ending rights that wrong or simply replaces one form of coercion with another is a question the play refuses to answer cleanly.

Hermia reveals Demetrius's possessiveness. He does not love her so much as refuse to relinquish her to a rival—a distinction Shakespeare makes clear by showing how quickly enchantment erases her from his desires entirely.

Lysander functions as Demetrius's mirror and sparring partner. Their near-duel in Act III is physically farcical but emotionally telling: two men willing to fight to the death over feelings they do not fully understand, following a fairy's whim.

Oberon holds absolute power over Demetrius's fate. That the King of Fairies—an external, supernatural authority—decides who Demetrius loves permanently extends the play's running theme that romantic desire is never entirely self-generated or rational.

Theseus and Egeus represent the institutional framework that initially empowers Demetrius. When Theseus overrides Egeus in Act IV and blesses all four unions, Demetrius's institutional advantage dissolves, and he is left entirely dependent on Oberon's enchantment for his happy ending.