This is an anthology of short stories, set in a shared universe, edited by George RR Martin (but note he does contribute stories as well as editing).
The Wild Cards universe begins in 1946, the same as ours up until that point, then an alien virus known as the 'wild card' virus is unleashed over New York. The majority of affected people die from the virus. Of those that survive; A small percentage gain deformities - extra limbs etc (these are known as Jokers), an even smaller percentage gain superpowers(these are Aces), and a very rare few known as Deuces.. have powers, but powers that are practically useless.
This first book in the Wild Card series, sets up the story of how the wild card virus came to be released, and the immediate results of it. Notable characters are Dr Tachyon, who is an Alien from the planet on which the virus orginated. The Four Aces, who were the first Aces then hired by the US government for special missions. And Jet Boy, the last pure human hero, who tried and failed to prevent the release of the virus.
Each story tells of an individual or group, and how their lives were affected by the wild card virus. Usually tragedy interspersed with moments of great triumph and magic. But each story is subtly (or not so subtly) connects to the others, I don't think any story is a complete stand alone from the others, but they could all be read as such, you'd just miss out a bit on the overall chain of events.
I started reading this series because George Martin is one of my favourite Authors, and I'd read some of his contributions to Wild Cards in his own Anthologies Dreamsongs: A RRetrospective: Book Two, but he's not the only good Author in here, all the stories are pretty good. But one of the best ones is by Roger Zelazny - 'The Sleeper' - this introduces the character Croyd, who is The Most imaginative character of all, he doesn't just have one set power, his powers change every time he goes to sleep.
There are about 20 books in the Wild Card series now, and I've yet to finish the 2nd, I think they're well worth continuing with, I think I just let loads of other books side track me.. but I'll be trying to finish more of them this year, hence reviewing the first one now :)