I have always been a huge fan of Grant Morrison, owning several of his other works, and the man has always delivered. After reading Supergods, I was thoroughly convinced that there will never be, nor has there ever been a greater writer than Morrison (except maybe Jack Kirby, of course). Whether it's taking the reins as the writer of the Caped Crusader himself, or even rebooting the X-men, he always has a firm grip on the lore behind the story, more so if the story is his own.
And that brings me to Flex Mentallo. Flex Mentallo, on the first and most basic level, is a story about a hulky muscle man brought to life by his own writer, brought into a world that desperately needs people like him. In a world where people are living in the streets and getting beaten up by gangs, Flex does his best to be the "Superman" of his world. The story, like many of Grant's terrific tales, can be a very disorienting ride, especially for newcomers to his work. Some will complain that the story is complex for the sake of being complex; another common criticism of Grant's writing style.
However, on a deeper level, you will learn that the story isn't just about Flex, it's about us. The series is broken down into 4 issues, and this is for a good reason.
The story is a commentary on the writing of comics as a whole. Flex Mentallo covers all 4 comic writing periods (Golden Age, Silver Age, Bronze (or Dark) Age and Modern Age). with each issue covering that theme through story arc, artwork, and general atmosphere.
You begin to realise that Flex's world is indeed our world, and what we are making of it. How comics are only depressing and gritty because people choose to make them that way, instead of bringing back the cheerful adventures of the Golden Age, or the weird and wonderful events of the Silver Age; when comics were for everyone.
If you have any interest in the writing and history of comics, I recommend you read this comic.
And hey, even if you don't, at least you get a bloody good story out of it.
EDIT: This is completely embarrassing, but I've only just looked this over and realised that I haven't mentioned Frank Quitely's artwork at all.
Frank is an incredible artist and always has been. His work with Grant is far and beyond his greatest, simply because the duo are the best one-two punch combo in the entirety of comics. His artwork on Flex reflects this, with every facial expression, hand gesture, action sequence and environment perfectly capturing exactly what the reader wants and needs to see with a story like this.
All Star Superman, WE3, New X-Men, Batman and Robin - if Grant is my favourite writer, then Frank is, without a doubt, my favourite comic book artist ever.