ok so i've been following green lantern on n off since childhood but most recently now. the events of final crisis and other story arcs have left some notable dc characters dead like aquaman,martian manhunter(first to die in final crisis actually),batman and even  darkseid. blackest night is essentially a prophecy of zombies(will explain later). elastic man and his wife,hawkman and hawkgirl,aquaman,aqualad and martian manhunter amongst countless others have been raised from the dead and initiated into the black lantern corps,plus bruce wayne's skull has been taken by the black hand who is their leader. their central power battery contains the body of the anti monitor and scar has turned on her fellow guardians,imprisoning them. now for the history:

in the book oa,the prophecy of the blackest night has been written and warned against,even by the light monks,but the guardians got blind-sided. now the war of light is upon them(almost over actually). all lantern corps of the emotional spectrum are both at war and under attack: green (will power) yellow(fear)red(hate)orange(avarice)blue(hope)indigo(compassion)violet(love)and the latest black(death). all have their strengths and weaknesses against each other but the black lanterns are for now the most powerful and the most unstoppable. the war of light is a trilogy that is thus far available in trade books. part one is green lantern rebirth(also green lantern secret origin,part two is green lantern sinestro corps war. their are two integral trades out that are prior to the last part of the trilogy which is currently the blackest night arc. those green lanter rage of the red lanterns an green lantern sins of the star sapphires. there should be another for the orange lanterns before they turn the blackestr night into a trade. that's all.  buy the books!