The Odyssey is about how Odysseus's survived the journey home from the Trojan War.
Odysseus is the king of Ithaca, with his wife Penelope and son, Telemachus. Odysseus had to leave home to the battle of Troy, and after the war he starts his journey back home. He goes to the Lotus-Eaters, and tells his men not to eat the Lotus and they spent a couple years there(the Lotus flower makes them lose track of time).
Then they were captured by the Cyclops, Polyphemus, then they escaped by blinding the cyclops with a wooded stake, and Odysseus told Polyphemus his identity(which was a stupid move) and fled. Later, Polyphemus told his father, Poseidon, that Odysseus has blinded him and Poseidon cursed Odysseus to wander in the sea for 10 years, while losing all his crew members, and return home with the help of others.
After the escape, Odysseus and his crew were staying with Aeolus(ruler of winds). He gave Odysseus a leather bag that held all the winds, except the west wind, as a present for a safe return home. Odysseus had informed his crew NOT to open the bag, but the eager crew members opened the bag while Odysseus was asleep, hoping there was gold, and all the wind came out and blew them off course.
All of Odysseus ships entered the harbor through the Laestrygonians' Island, except his, and were all destroyed. Odysseus continued and went to visit the witch-goddes Circe. She turned half of his men into swine after feeding them cheese and wine. Hermes informed Odysseus about Circe magic and gave him a drug/potion called moly which resisted Circe's magic. Circe, surprised by the resistance, agreed to change his men back, for his love. So they stayed at the island for a year.
Then Odysseus and his crew crossed the ocean and arrived at a harbor at the western edge of the world, and was sacrificed to the dead. He went to the UnderWorld to talk to find out how to go home, but the person who knows was from the Trojan War, but he was on Trojan side, not the evading Greek side(theres a whole another story behind that).
After Odysseus comes out of Heidi's, they will pass the land of the Sirens. The Sirens will sing their songs, and the sailors would come crash into the rocks, and their ships would break, and the Sirens would eat them, thats what they do. Odysseus knows the story, so he wants to be the only man alive that knows the song. So he has all of his men put beeswax in their ears, so they can't hear it, and tied himself to the mast. And as they pass by it he would be the only man to ever hear the song and live to tell the tale.
They passed by the 6-headed monster Scylla, and the whirlpool Charybdis. And Scylla took 6 men.
The rest of the men landed on the Isle of Helios and they are starving, and all the cattle's were protected by, Helios(the sun God). So, the men are starving and they ended up killing a cow, then Zeus sent a lightning bolt to Odysseus' ship and they were shipwrecked, as they were going down, Charybdis. Everyone drowned except Odysseus, who was hanging on a fig tree above the whirlpool. And then he was washed away to the island of Ogygia, and stayed as Calypso's lover, till ordered to let him go by Zeus.
And when he finally got home to the Island of Ithaca, he disguises himself, and goes in his house, which is filled with suitors trying to marry his wife, since he was gone for about 2 decades. And there's another story about how he wins back his kingdom, his wife, and family.