Earth is celebrating the 20th Anniversary of winning the '96 War against the invaders. In those twenty years humanity has adapted the alien technology. Not only have humans stopped having war amongst themselves, they have a base on the moon. This is where we meet pilot Jake (Liam Hemsworth), who is the fiance of former President Whitmore (Bill Pullman) daughter, Patricia. Another new character is Dylan, who is friends with Jake and Patriicia, though he has a beef with Jake. He's Will Smith character's son (it's explained that Smith's character died in a test flight). There's also President Lanford (Sela Ward) and General Adams (William Fichtner).
While Jake and the others are on the moon base as part of the 20th celebration, a new ship arrives through what looks to be a wormhole. They think it a threat, so they blow it up. It turns out to be an ally, though. Then, the invaders from the first movie show up in a massive ship that's over 3000 miles in diameter. It lands over the Atlantic ocean and begins drilling down to the Earth's core. They learn that these aliens use the molten core of planets for their ship's energy source and end up destroying all life in the process. David Levinson (Jeff Goldblum) is back at Area 51, trying to figure out how to stop this new threat and Dr. Brakish Okun (Brent Spiner) awakens from his twenty-year coma, all ready to help out with his crazy inventions.
After I saw this in the theater I re-watched the original, remembering that the original was a better film. But, in truth, this is the superior movie. This sequel does a good job of continuing some of the characters and also goes in a totally different direction than the first. If there's a Part 3 it will be even more different. This movie begins as an alternate reality tale and veers into, basically, a giant monster film. What this reminded me the most of is the animated film, WAR OF THE WORLDS: GOLIATH, which is actually a better film than both INDEPENDENCE DAY movies.