In this movie, Truman Burbank (Carrey) is raised from a baby in a completly controlled and filmed environment. The city of Seahaven appears to exist on the Florida Panhandle, but in fact is encased in a giant dome behind the Hollywood sign. On top of the dome is the Lunar Room where the show's Director/Creator Christof (Ed Harris, A Beautiful Mind) conducts Truman's daily events. His job consists of everything from camera angles, mood music and handling any unexpected manuevers made by Truman or the cast members.
When the film starts off, Truman is married to Meryl (Laura Linney, The Exorcism of Emily Rose), is best friends with Marlon (Noah Emmerich) and seems to be living the perfect life, and everything seems to have the same feel as the stereotypical 1950's TV family, short of the kids that Truman doesn't have (but Christof is determined to give him soon). Truman isn't completely settled with this uber-perfect life. Instead, he constantly remembers a brief encounter he had with Lauren (Natascha McElhone from Californication) in college who insisted everything around him was fake and no one should be believed. Their brief encounter has her whisked away and supposedly transported to Fiji on the other side of the world.
Truman spends his days longing for a chance to reconnect with her and adventure outside of Seahaven. Meanwhile, Christof and the cast constantly find ways to keep him satisfied with his current location, or keep him there by fear. A good example of this is when Truman lost his father to a frightful storm in the bay, which led Truman to fear water ever since. This simple feat has kept him off of the boats and unable to cross the river that circles the city. But when his dad suddenly reappears as a bum on the streets (only to be pulled out of sight by everyone around him), his desire to find out exactly what is going on gets stronger than ever.
Truman starts to suspect just a few people to be in on whatever is going on. He thinks it simply has something to do with his dad at first, but soon comes to realize it is much bigger than that. Starting with his own wife, his mistrust starts close to home, but then spreads to everyone until his eventual escape attempt.
The cinematography of the movie typically has you watching Truman's world through the 5,000 or so hidden cameras as if we are watching the show itself. There are also times when we cut to the various viewers of the show who live their lives around the The Truman Show.
The Truman Show, which was Carrey's first attempt to break out of his comedic roles, really feels liked a strange Sociology and Psychology experiment gone awry wherein we get to see how a person can react while growing up in a completely contained and controlled environment and he finds out that nothing around him is real (except, as Christof point's out, he, Truman, is real in the show).
Special Features like the two part "How's it Going to End?" featurette and "Faux Finishing" both go into a lot of details about what went into the movie (both the subtle special effects and the writing and directing). But there doesn't seem to be any new features for this particular release, then again the latest DVD version only came out a couple of years ago. So while the special features really do give you a lot of insight into the making of the movie, they themselves are still in standard definition (which means you will probably have both letter boxing and black bars on the left and right of the image), which can get annoying.
I've been a big fan of The Truman Show since I first saw it some 10 years ago. It's just a fun ride to see Truman go from this everyday person in a sheltered life to someone who becomes paranoid and starts to act a bit crazy, but never really questions his own opinions on what's going on around him, even when Christof pulls out his biggest and most moving pieces of dialogue. As for the need to upscale it to the higher definition, usually I don't see the need for a film with so few (obvious) visual effects to be put into high definition so early in the media's life cycle, but the amount of detail you can see on the actor's faces (not to mention McElhorne's eyes when Truman stares into them during their brief encounter) really helps to sell high definition in general.