No. 5: "Cast Away" (2000)
This is arguably the purest beach movie ever made -- a film in which the beach itself is a major character -- the chief antagonist to Tom Hanks' character Chuck Noland.
After a shockingly bone-jarring plane crash, the movie plunges into scenes devoid of dialogue as Noland struggles with the beach for survival. He desperately tries to open a coconut, spells out HELP in huge letters in the sand and ultimately learns to spear fish.
Gradually, Noland fades into the scenery as he transforms from a tubby time-obsessed FedEx analyst to a gaunt but savvy denizen of the beach -- a natural part of the sandy landscape.
An obvious honorable mention for another movie in which the beach itself played a starring role would be "The Blue Lagoon" (1980), with a lush setting so beautiful it was upstaged only by Brooke Shields and earned an Academy Award nomination for cinematography.