If you liked Being John Malkovich, Adaptation, and Eternal Sunshine of the Spotless Mind -- all written by Charlie Kaufman -- you owe it to yourself to see his directorial debut, at least once! Kaufman has done an excellent job of directing a fine ensemble cast, with production design that makes the whole story realistic despite the dreamlike way events unfold. The result has plenty of emotional impact, if you don't get too distracted and disoriented by the hallucinatory qualities of the story.
One of the running gags in the film is the director's absurd attempts to come up with a title for his creation, which grow more and more absurd, and never arrive at the actual title of the film. The "Synecdoche" of the title refers to a figure of speech in which the name of a part represents the whole, and you'll see how that fits; but it's also a pun, because the story begins in Schenectady, New York. This invites comparison (in the literary world) with Joyce's Finnegans Wake, and both seem to give us a whole lifetime compressed (or repressed?) into a single dream; but the characters here don't shift identities as much as they do in FW, and Kaufman doesn't play with the language in Joycean fashion. The dialogue is plain as day, often very memorable and very funny, but it throws its light on a story with all the quirky twists and turns that you'd expect from a writer like Kaufman. Like Adaptation, this is a portrait of the artist (in this case a theatre director/playwright) at work on an oddball project, but here it grows to impossible proportions.
It's also like David Lynch's Inland Empire (and Mulholland Drive) in being a drama about movie-making where the lives of the actors and the characters they play become inextricably and inexplicably entangled. This kind of film certainly isn't for everyone, but if you enjoy watching the boundaries between life and art, or dream and reality, dissolve, then it's for you.