No group is better suited to bring the spirit of Spinal Tap to life than Anvil. Thanks to last year’s sleeper-hit documentary Anvil! The Story of Anvil, the scrappy Canadian metal band is bound to generate hype for years to come — an unexpected coup, indeed. A perpetually beleaguered act, Anvil arrived on the metal scene in the early ’80s, in time to influence some of the genre’s heaviest hitters before fading into obscurity. To fair-weather fans (drawn by the allure of taking ironic pleasure), take notice: Bandleaders Lips Kudlow and Robb Reiner are laughing, too. Newer lyrics such as life can be just like a Game Boy, filled with frustration and joy prove that, for Anvil, overthinking is still — happily — not a problem.