What's it all about?
It all sounds pretty humdrum on the face of it - the story of an ordinary American boy called Mason (played by newcomer Ellar Coltrane) and his life growing up in the suburbs between the ages of 6 and 18.
What makes it special then?
Here's the thing: it was filmed in real time over a 12-year stretch, so the cast of characters - Mason, his sister Samantha (Lorelei Linklater), Mum (Patricia Arquette) and Dad (Ethan Hawke) - grow with the film, with no need for the usual make-up tricks, sped-up montages or swapping in of actors halfway through.
So they filmed it for 12 years straight?
No! In fact it was filmed in just 39 days, but those days were spread over a period of 12 years, with the actors meeting for a few days of filming each year. In the mile-a-minute world of Hollywood, getting a cast of actors to commit to such a long-term project (with no real guarantee it'll work) is no mean feat, and possibly explains why Linklater cast his own daughter Lorelei to play Mason's sister Samantha. Also, the whole movie was done on a tiny budget. As Patricia Arquette put it this week: "I paid my dog-walker more than I made on Boyhood."
So what happens?
Don't expect any wild story arcs or improbable plot twists. The film is in fact all the better for its ordinariness (though there are a few dramatic bumps in the road, Mason has to bounce between his separated parents and there's a brief stint with an alcoholic step-father) but it's the steady drip of Mason's life, and those ordinary anti-Hollywood bits of growing up we all identify with, which make the whole thing so special.
Who steals the show?
Patricia Arquette is brilliant as Mason's mother and now has a well deserved best supporting actress Golden Globe on her mantlepiece to show for it. Her role in the film also inspired one of our favourite jokes at the Globes on Sunday night from host Amy Poehler: "Boyhood proves there are still great roles for women over 40, as long as you get hired when you're under 40." Ellar Coltrane as Mason was a pretty huge casting gamble - given he won the part aged 7 - which thankfully pays off. After all, it's not like a normal movie where you can go back and re-shoot earlier scenes.
Will it win the best film Oscar?
The Golden Globes are normally a pretty strong indicator of how the wind will blow awards-wise, and Boyhood scooped the biggies on Sunday: best film and best director. That said, with the hotly tipped Birdman in the mix there's still all to play for. Watch this space.
Scroll down to watch the Boyhood trailer