One of Our Thursdays Is Missing

With the real Thursday Next missing, the "written" Thursday Next leaves her book to undertake an assignment for the Jurisfiction Accident Investigation Department, in Fforde's wild and wacky sixth BookWorld novel (after Thursday Next: First Among Sequels). As written Thursday Next finds herself playing roles intended for her real counterpart, BookWorld's elite try to deal with a border dispute between Racy Novel and Women's Fiction. It's not always possible to know where one is in BookWorld, which has been drastically remade, or in Fforde's book, which shares the madcap makeup of Alice in Wonderland, even borrowing Alice's dodo. Outrageous puns (e.g., a restaurant called Inn Uendo) and clever observations relating to the real book world (e.g., the inhabitants of "Vanity" island now prefer Self-Published or Collaborative) abound. Fforde's diabolical meshing of insight and humor makes a "mimefield" both frightening and funny, while the reader must traverse a volume that's a minefield of unexpected and amusing twists. 10-city author tour. (Mar.)