Undead refers to vamps, not zombies & if you can follow the convoluted plot (I recommend reading the Wikipedia summary & then watching the movie), then Rosencrantz & Guildenstern Are Undead is hilarious. Best side joke is L&O’s Jeremy Sisto who plays a bumbling detective. Would particularly recommend Rosencrantz & Guildenstern Are Undead to theater geeks & vamp lovers.