It's the same protected Brooklyn Alley but Hugsy is now a bearded college student and the narrator-hero of this belated sequel is Nicky Carroll, now an improbably young eleven. It seems that Hugsy has once hinted that there might be an underground tunnel beneath the alley, and after considerable secret digging -- punctuated by friction with the ""contamination"" (girls) and a few fearful encounters -- Nicky (or Copin, as he calls himself) and his eight-year-old friend Timmy Fabian (or Tornid) discover that Hugsy was indeed correct. (ESP?) It takes Hugsy's fortuitous visit to his ""old haunts"" to wind up the plot and make heroes of the boys, but nothing can make the alley what it used to be. For one thing the circle is gone (made into gardens by adjacent residents) and instead of Connie's playground paradise the enclosed faculty row is more like a cage to Copin and Tornid. Mrs. Estes, too, has some trouble adjusting to change, as is illustrated in her frequent allusions to the Beatles' ""It was a long day's night"" (sic). Despite Hugsy's beard, some up-to-date slang, messages in psychedelic chalk, and a letter from ""Mayor Woolsey,"" a complacent, ivy-covered tranquility still adheres to the college and its teachers, while the faculty wives (Copin calls them ""the Moms"") spend their time drinking coffee, chatting over the fences, and making gleeful sorties to the Job Lots. An early episode in which Copin and Tornid escape the alley for a forbidden (first) ride on the doomed Myrtle Avenue el has the charm and humor of Estes' old (enduring) grasp of a child's-eye view, but whereas The Alley in 1964 set a real crime in a happily safe and cozy setting, The Tunnel plants a series of scares, with disappointingly innocent explanations, in the tight little academic community that now seems unconscionably isolated. In the end Copin, his family moving to Vermont, says good-bye to the alley -- and we can't help Feeling that the time has come.