The Cyclops Polyphemus
On his way back from the Trojan War, Odysseus and his army land on the island of Polyphemus, who is a Cyclops, a one-eyed giant son of Poseidon and Thoosa in Greek mythology. It is one of the instrumental characters that define the course of the film and the journey of Odysseus

The Sirens 
Apart from Polyphemus, the Sirens are also the most fascinating characters that you will encounter on another island in the film. The creature is known to be dangerous as they enchant sailors and lure them towards their deaths 

Circe 
One of the other most fascinating creatures is the enchantress Circe, who is known to be very powerful, and when Odysseus and his men come on her island, she turns them into pigs, to depict the greed of men 

Calypso 
While these are fleeting characters, Calypso played by Charlize Theron is one of the most interesting figures that is seen throughout the film, as the nymph holds Odysseus captive on her island for years, and feeds him the white lotus flower

Scylla and Charybdis
After passing the Sirens, Odysseus and his crew meet the two terrifying monsters in the sea - Scylla and Charybdis. While Scylla is the six-headed beast depicted as a mountain, Charybdis is a enormous and dangerous whirpool

Tiresias
While all of these are different kinds of creatures, Tiresias of Thebes, one who is known to help Odysseus in the Underworld