However irregular his turning up in the 13th century, newly infatuated with Nimue, Merlin's mistake is conceived otherwise: distractedly (Nimue again) blessing Tertius, son of Sir Baldwin of Bedegraine, he has endowed him with all future knowledge. ""Future?"" puzzles newly-met Brian, son of Sir Owaine of Caercorbine. ""Yes,"" affirms Tertius, ""do you know what a nuclear reactor is?"" Proceeding through ""a tangle of bracken. . . copse of beeches. . . patches of gorse"" (four lines' worth of Anglo-sacking) in a never-never land where Camelot and the Crusades coexist, this is a mishmash of demi-legend and quasi-history sporadically emitting a weird sense of humor (as when Stonehenge turns into a bank of computers). As lackadaisical Sir Uriel allows, ""You can't win 'em all.