One of the frescoes depicts a meeting between Helen and Paris, son of the Trojan king, Priam, identified by a Greek inscription of his other name, “Alexandros.” In Greek mythology, Paris ...

He gathers the Greek leaders and they arrive in Troy to deliver an ultimatum to King Priam: return Helen immediately or it's war! Menelaus returns to find that Helen has gone to Troy with Paris.

Then the Greeks sail to Troy and hand King Priam their ultimatum: return Helen plus compensation or Troy will be destroyed.