The author of ”The Butcher Boy” clearly has a soft spot for head cases. And the utter unreliability of his eighth novel’s narrator — a troubled cross between Travis Bickle and Chauncey Gardiner — ensures you won’t quickly know which way Call Me the Breeze is blowing. What begins dryly as a fictional memoir of apparently successful Irish author Joey Tallon becomes a psycho-thriller when he recounts disastrous incidents of stalking and kidnapping. Just when the book threatens to get really dark, it turns into an all-out comic romp as Joey, like the heroes of ”Taxi Driver” and ”Being There,” is mistaken for something other than the wack job he is. Subplots involving IRA murders and Bono jokes add Irish spice, but this very funny story is universal enough that some of Joey’s modest delusions of grandeur might hit close to home, even for us non-nutters.