Berserk

This is my favorite series of all time.  I must have read the manga all the way through at least 4 times (all 36 volumes that are available anyway).  The art is spectacular, the story is engrossing, the characters are all people I’d love to meet (except for Griffith, what an asshat; and Corkus, too).  In any case, I couldn’t recommend any series more highly than this one.  The only thing that breaks my heart is that the author will likely never finish it because it’s been going on for 20+ years and there is still no end in sight.