All of the hallmarks of a New Pornographers disc - layered arrangements, lush harmonies, tons of lovingly deployed '60s and '70s references - are present and accounted for on their fourth album. There's greater depth, too, as it seems like bandleader and chief songwriter A.C. Newman has been working through some changes. Up-ending the apple cart is great for the muse, and Challengers finds him plunging "Unguided" into an uncertain future of new experiences, new love, and New York. On the down side, the album doesn't quite cohere as a whole, and the derivations can still be a little too obvious. For instance, take "All the Things That Go to Make Heaven and Earth": As pleasurable a piece of pomp as it is, could it be any more Roxy Music-esque? Still, songs like "My Rights Versus Yours," "Mutiny, I Promise You," and especially "Go Places" are pure musical ambrosia: dreamy, high-concept pop that tickles the ears, lingers in the mind, and aims for the stars.