Ah, the "what if" yarn. What a great genre. Well, it's great when it's done well at least - like Philip K Dick or Robert Harris positing an alternate history where the Axis powers won the Second World War (in The Man in the High Castle and Fatherland respectively).
Arguably, comic books are all alternate histories - the main Marvel and DC universes are basically versions of our universe, but with super-powered individuals. But within these worlds, alternate versions are constantly rearing their heads, being killed off, being cloned, or being tidied up by crossover events (such as DC's 'Crisis on Infinite Earths' and Marvel's 'Secret Wars').
Marvel has previously done some excellent things with its characters in terms of giving them alternate futures. Among the Marvel alternate futures are some supberb entries in the X-Men cannon: most famously with 'Days of Future Past' and 'The Age of Apocalypse'. 'Old Man Logan' is yet another entry in this sub-sub-genre, featuring alternate futures for Marvel's heroes.
Written by Scotsman Mark Millar (The Authority, Civil War) and illustrated by Canadian Steve McNiven (New Avengers, Civil War), it introduces a future where, much like in Millar's earlier comic-book wanted, the super-villains have simply combined forces and wiped out the outnumbered superheroes. Well, most of them. Among those they leave alive is Wolverine, who has been psychologically broken. How he was broken forms one of the main strands of the narrative, but the actual storyline concerns Wolverine - now simply a husband and father called Logan - being offered a job by fellow survivor Hawkeye (Clint Barton), now blind but still formidable with ranged weapons.
Logan and his family are being threatened by their landlord - one Bruce Banner, aka the Hulk, who has (in-)bred with his cousin, She-Hulk, and created a scary brood of hard, green hicks to be his personal army of enforcers in his kingdom, in the former Mid-west. As he's in danger of getting behind in his rent, Logan is forced to take the job navigating Barton across a post-apocalyptic USA to make some sort of illicit delivery.
To say too much more would spoil the fun. Well, sort of fun, as this is pretty grim stuff. There's plenty of excitement, but it's a deeply unpleasant adult take on the future of the Marvel Comics Universe. Millar's clearly been inspired by gritty Westerns here. A lot of it takes place in the sort of backcountry frequented by Clint Eastwood's Man with No Man, or even John Wayne's man with a name - Ethan Edwards - in The Searchers. But it's also distinctively Millar. Millar's great at scenarios, great with characters, and great at the harsh or macabre stuff, but his storytelling can get a bit bitty and confusing in places. Not so much to undermine the excellence of Old Man Logan though, which is packed with wonderful details (look out for Pym Falls, among other things). Niven's artwork describes all this horror neatly and precisely, with suitable sobriety, until it reaches the unforgettable climactic showdown feature Logan and his former scientist turned monster hillbilly patriarch landlord. Say no more.