Helen is a drama by Euripides, probably first produced in 412 BC for the Dionysia. The play shares much in common with another of Euripides' works, Iphigeneia in Tauris.
About thirty years before this play, Herodotus argued in his Histories that Helen had never in fact arrived at Troy, but was in Egypt during the entire Trojan War. The play Helen tells a variant of this story, beginning under the premise that rather than running off to Troy with Paris, Helen was actually whisked away to Egypt by the gods. The Helen who escaped with Paris, betraying her husband and her country and initiating the ten-year conflict, was actually a phantom look-alike. After Paris was promised the most beautiful woman in the world by Aphrodite and he judged her fairer than her fellow goddesses Athena and Hera, Hera ordered Hermes to replace Helen, Paris' assumed prize, with a fake. Thus, the real Helen has been languishing in Egypt for years, while the Greeks and Trojans alike curse her for her supposed infidelity.
In Egypt, king Proteus, who had protected Helen, has died. His son Theoclymenos, the new king with a penchant for killing Greeks, intends to marry Helen, who after all these years remains loyal to her husband Menelaus.
Helen receives word from the exiled Greek Teucros that Menelaus has drowned, putting her in the perilous position of being available for Theoclymenos to marry, and she consults the seer Theonoe, sister to the king, to find out her husband's fate.
Her fears are allayed when a stranger arrives in Egypt and turns out to be Menelaus himself, and the long-separated couple recognize each other. At first, Menelaus does not believe that she is the real Helen, but luckily one of his sailors steps in to inform him that the false Helen has disappeared.
The couple still must figure out how to escape from Egypt, but fortunately, the rumor that Menelaus has died is still in circulation. Thus, Helen tells Theoclymenos that the stranger who came ashore was a messenger there to tell her that her husband was truly dead. She informs the king that she may marry him as soon as she has performed a ritual burial at sea, thus freeing her symbolically from her first wedding vows. The king agrees to this, and Helen and Menelaus use this opportunity to escape on the boat given to them for the ceremony.
Theoclymenos is furious when he learns of the trick and nearly murders his sister Theonoe for not telling him that Menelaus is still alive. However, he is prevented by the miraculous intervention of the demi-gods Castor and Polydeuces, brothers of Helen and the sons of Zeus and Leda.