Richelieu plots, Louis XIII is a moron and his wife Anne is underused. The annoying hoodrat D'Artagnan shows up to annoy and for unknown reasons (aka The Plot Demands it), the three musketeers befriend him. They unite to preserve the Queen's honor from the slurs of Richelieu and the Elvis quiff sporting baddie Buckingham (Orlando Bloom).
Buckingham wears OTT bling and preens. He is a villain you want to see slapped down but no, that'll have to wait for the sequel that is set up in the cliffhanger final scene. The real noteworthy character is Milady. She pouts, swordfights, does gymnastics, lies, steals, seduces and generally entertains. She also shows off an impressive wardrobe.
The plot such as it is involves Da Vinci, airships and an amazingly tacky looking diamond necklace. There's a fat bloke who is used for comic relief and Constance is an amazingly wooden love interest for the hoodrat D'Artagnan. It's better than the dreadful 1993 version but not on par with my fav Dumas adaption, the 1998 'The Man in the Iron Mask'.
It looks good but D'Artagnan is a loathsome hoodrat, Orlando Bloom does not feature enough and the post modernist dialogue grates after a while. It is not as good as it could have been and the 3D is unnecessary and there are nasty touches of sexism.