The plot follows Ben Randall (Kevin Costner) and Jake Fischer (Ashton Kutcher) at the United States Coast Guard's Aviation Survival Technician (AST) Program.
Randall is the top rescue swimmer who continues to work against regulation past the age of 40. Fischer is a hot-shot candidate for AST who was ranked as a top competitive swimmer in high school with scholarships to every Ivy league college and university but opted to enlist in the Coast Guard.
The film's title is introduced by a mythic tale: people lost at sea often claim they feel a presence lifting them to the surface, breathing life into their bodies while they are waiting for help to arrive. They call this presence "The Guardian."
The film earned $18 million on its opening weekend, and almost $95 million worldwide by January 4, 2007.
The Guardian received average reviews: Rotten Tomatoes currently has it at 37% rotten (141 reviews: 52 fresh, 89 rotten) while Metacritic rates it a 53/100 based on 29 reviews.
Stephen Hunter pans it in The Washington Post, calling it "a good little film" for the first hour then it "begins to overload its frail reed of a structure with giant sloppages of cliches from other movies, some so bad it's almost comical", concluding that the movie "veers off into slobbery touchy-feeliness, and the tone becomes mock-religious, almost liturgical." Wesley Morris of The Boston Globe called it "dutiful but dull."
For The New York Times, A.O. Scott notes that participation by actual members of the Coast Guard "lends an air of authenticity" and concludes "[i]t’s not a great movie, but it’s certainly one of the finest Coast Guard pictures you’re likely to see anytime soon."
In a Variety review, Joe Leydon says the movie is "overlong but [the] involving drama has obvious cross-generational appeal."
Ed Blank in The Pittsburgh Tribune-Review acknowledges there is plenty to snipe at yet also adds The Guardian "regurgitates formulaic elements in a way that pays off repeatedly and potently.