It had been said many times that Watchmen, perhaps the greatest graphic novel ever written, could not be filmed. When I first watched Zach Snyder's adaptation, I had not read the iconic source material by Alan Moore & Dave Gibbons. I enjoyed it then, as to me an original piece of work. Three years on, I've now read the book so watching the movie it becomes clear that it always was film-able - no one before Snyder perhaps had the balls. It's a huge undertaking that the divisive director takes, runs with and in the process delivers his finest film to date.

It's one of the most faithful adaptations of anything you could hope to find, as it turns out. Snyder understands that Gibbons artwork is so perfect, he can practically use it as a storyboard; his shots frequently match the artwork, creating an experience for any Watchmen fan that translates to literally seeing the work on screen. Similarly the screenplay quite often takes Moore's words, again close to perfect, and throws them in as dialogue. Were it a poorer book, this would never have worked but Snyder treats the text with reverence, proving it lends itself actually quite well to a visual narrative. He cuts out some elements (Max Shea & the Tales of the Black Freighter are completely omitted) while perhaps his biggest change comes in the ending, tweaking Ozymandias' grand plan from an alien monster to a Dr Manhattan-sourced weapon (to be honest, I actually feel that's a better choice - the ending of the book goes a bit mental) but for the most part, he keeps the central spine of the piece; he retains the Cold War paranoia, the fear of Soviet attack; he keeps the despotic and dark backstories of Dr. Manhattan, of Rorschach, of the Minutemen (telling their story over the credits, and the choice of music, is inspired); and he manages, like the book, to make a myriad of different characters, settings and ideas come together. I don't know if, despite its epic reach, it needed to be so long - nor am I completely sold on all of the casting. Jeffrey Dean Morgan, Carla Gugino, Jackie Earle Haley - all spot on. Billy Crudup can't act so he's fine for the monotone Manhattan too, as is Matthew Goode on calm form as Veidt. Yet Malin Akerman & Patrick Wilson feel wooden as our leading pair, though it could be their characters are the least interesting (and lets forget the horrendous sex scenes Snyder decides to lob in there between them).

Credit has to be given to Snyder though for making Watchmen in the first place, an unenviable task given how venerated the source material is. Probably because of that, it's his strongest film - directed faithfully with stunning visuals and attention to detail, excellent portrayal by and large of the characters and he keeps all of the best components of Moore & Gibbons work in. It's too long but Watchmen needed to be epic and, truthfully, I doubt anyone could make a better, more loyal adaptation than this.