<P> Camp Half - Blood is under attack when Thalia's tree, which guards the borders of the camp, is poisoned and slowly begins to die . In order to save the tree and the camp, someone must recover the Golden Fleece, which is somewhere in the Sea of Monsters . At the same time, Percy finds out that Grover, who has left on a quest to find the missing god Pan, has been captured by the cyclops Polyphemus and that the Fleece is on Polyphemus' island . Together with Annabeth and his half - brother Tyson, a cyclops, Percy sets out to rescue Grover . Meanwhile, Clarisse La Rue, daughter of Ares, is sent on an official quest by Camp Half - Blood to retrieve the Fleece . The trip to the Sea of Monsters is long and hazardous and along the way the heroes encounter several dangers including Scylla and Charybdis, the sorceress Circe, the Sirens and their former friend Luke Castellan . Percy also learns about a prophecy from the Oracle about a child of one of the three most important gods (Zeus, Poseidon and Hades), playing a vital part in the success or failure of the resurrection of Kronos the Titan - King . The heroes eventually retrieve the Fleece and restore Thalia's tree but also unknowingly revive Thalia herself, daughter of Zeus, who had been turned into the tree by her father when she died . </P> <P> The book was adapted into a film by Thor Freudenthal and 20th Century Fox, under the title Percy Jackson: Sea of Monsters, and was released on August 7, 2013 . </P> <P> The Titan's Curse is the third installment in the series . It was released on May 11, 2007 . </P> <P> On a mission to rescue half - bloods Bianca and Nico di Angelo; Percy, Annabeth, Thalia and Grover are attacked by a manticore and rescued by the goddess Artemis and her Hunters . However, Annabeth falls off a cliff whilst trying to fight the manticore and is said to be captured . Later, Artemis is captured by Luke's army while on the hunt for the Ophiotaurus, a cow - serpent monster that was foretold to bring the downfall of Olympus when its entrails are sacrificed to a fire . Her lieutenant Zoe Nightshade, daughter of Atlas, leads Bianca, Thalia and Grover on a quest to save her . Percy, who was not invited to join the party, follows them on behalf of Nico Di Angelo, promising that he will do his best to protect his sister, Bianca . The others eventually find Percy, and he joins their group . They become the prey of skeletons, who chase them across the country . Bianca is able to kill one, which leaves the others mystified . Bianca later dies as they make their way across a godly junkyard . They find Annabeth with Luke and Artemis, who is holding up the sky . Percy then takes it from Artemis and they trick Atlas into his original position under the sky . Thalia replaces Zoe, who dies, as Artemis' lieutenant . Thalia's induction as a lieutenant of Artemis ensures that she will become immortal, never aging to 16, thus escaping the Great Prophecy and leaving Percy to fulfill it . They return to camp and Percy informs Nico about Bianca's death during the journey . Nico blames Percy for failing to protect her and runs away, only after killing skeletons that invade the camp, so that Percy realizes that Hades is Nico's father . </P>

What's the third percy jackson book called