<P> Perseus befriends Thallo and presents himself as suitor and correctly answers the riddle, presenting the severed hand of Calibos . Perseus wins Andromeda's hand in marriage . Finding that Thetis cannot act against Perseus, Calibos instead demands that she takes vengeance on Joppa . At the wedding, Queen Cassiopeia compares Andromeda's beauty to that of Thetis herself, whereupon Thetis demands Andromeda be sacrificed to the Kraken on pain of Joppa's destruction . </P> <P> Perseus seeks a way to defeat the Kraken, while Pegasus is captured by Calibos and his men . Zeus commands Athena to give Perseus her owl Bubo; but she orders Hephaestus to build a golden replica of Bubo instead, who leads Perseus to the Stygian Witches . By taking their magic eye Perseus forces them to reveal that the only way to defeat the Kraken is by using the head of Medusa, who lives on an island in the River Styx at the edge of the Underworld . The next day, the group continues on their journey without Andromeda and Ammon, who return to Joppa . </P> <P> On the Gorgon's island with three soldiers by his side, Perseus fights Medusa's guardian, a two - headed dog named Dioskilos, who kills one of his companions but Perseus intervenes in the nick of time and kills the beast . Perseus leads his two remaining allies into the Gorgon's lair . His two other companions die on encounter with Medusa herself; she shoots one of the soldiers with an arrow and turns the other to stone . Perseus uses the reflective underside of his shield to deceive Medusa, decapitates her, and collects her head; but the shield is dissolved by her caustic blood . As Perseus and his party set to return, Calibos enters their camp, forces Bubo into the water, scares the horses away, and punctures the cloak carrying Medusa's head, causing her blood to spill and produce three giant scorpions called Scorpiochs . The scorpions attack and Thallo is able to kill one of them, but he and his fighting companion are both killed by Calibos himself . Perseus slays the other two scorpions and thereafter kills Calibos and grieves Thallo's death . </P> <P> Weakened by his struggle, Perseus sends Bubo to rescue Pegasus, who is being held prisoner by Calibos' henchmen . Bubo succeeds in his task and manages to destroy Calibos' camp as well . Perseus reaches the amphitheater in Joppa, but collapses unconscious from exhaustion . Andromeda is shackled to the sea cliffs outside Joppa, and the Kraken itself is summoned . Bubo diverts the Kraken's attention until Perseus, whose strength was secretly re-restored by Zeus before the Kraken was released, appears on Pegasus . In the subsequent battle, Perseus petrifies the Kraken with Medusa's head, causing it to crumble to pieces . He then tosses the head into the sea, frees Andromeda, and marries her . </P>

Who played andromeda in clash of the titans