Year three at Hogwarts means new fun and challenges as Harry learns the delicate art of approaching a Hippogriff, transforming shape-shifting Boggarts into hilarity and even turning back time. But the term also brings danger: soul-sucking Dementors hover over the school, an ally of the accursed He-Who-Cannot-Be-Named lurks within the castle walls, and fearsome wizard Sirius Black escapes Azkaban. And Harry will confront them all.

After years of increases in the greenhouse effect, havoc is wreaked globally in the form of catastrophic hurricanes, tornadoes, tidal waves, floods and the beginning of a new Ice Age. Paleoclimatologist Jack Hall tries to warn the world while also shepherding to safety his son, trapped in New York after the city is overwhelmed by the start of the new big freeze.

In year 1250 B.C. during the late Bronze age, two emerging nations begin to clash. Paris, the Trojan prince, convinces Helen, Queen of Sparta, to leave her husband Menelaus, and sail with him back to Troy. After Menelaus finds out that his wife was taken by the Trojans, he asks his brother Agamemnon to help him get her back. Agamemnon sees this as an opportunity for power. They set off with 1,000 ships holding 50,000 Greeks to Troy.