Beat the heat with a blockbuster

>>> beach, barbecue, and box office . memorial day weekend means the start of the summer movie season. and hollywood is hoping for the biggest summer ever. nbc's miguel almaguer has our preview.

>> reporter: hollywood hopes to start summer off with a bang.

>> you're in my world now.

>> reporter: this weekend kicks the blockbuster movie season into high gear . action-packed big-budget new releases hit the silver screen just in time for the holiday. the stage set for hollywood to make --

>> the ship is ours!

>> reporter: -- a boatload of money.

>> the summer of 2011 is shaping up to be the biggest box office summer of all time. if it breaks $5 billion, it will break last year's record. and i think it has a really good chance of doing that.

>> reporter: the studios are banking on the summer of sequels.

>> i think it's happened again.

>> reporter: there's "the hangover 2," "transformers 3," "pirates 4," and "fast 5."

>> by and large, sequels are more expensive to make for the hollywood studios, but they're also the safer bet.

>> reporter: those sequels come just at a time when hollywood could use a bit of a bounce. box office receipts were down 20% at the start of this year. but that's likely to change this summer . the studios have released something for him --

>> oh, holy -- where are we?

>> reporter: something for her.

>> i'm engaged.

>> oh, my god!

>> reporter: and plenty for the kids.

>> my fist hungers for justice.

>> reporter: but one movie's expected to cast the biggest spell at the box office .

>> we'll finish this the way we started.

>> reporter: the eighth installment of " harry potter ," the most successful franchise of all time, hits theaters this summer . alone, it could gross $400 million. now, that's box office magic. miguel almaguer, nbc news, hollywood .