Releasing a "mature" followup to their acclaimed 2003 debut could have been a total disaster for ex-Unicorns Nick Diamonds and Jaime Tambeu. Considering that the Montreal group's unpredictable song structures and amateurish, lo-fi charm were what initially earned it so much praise, the decision to disband the Unicorns, start anew as Islands and release a comparatively traditional indie-pop record was certainly a gamble. But judging by Return to the Sea, Islands' debut, the risk has more than paid off. On Sea, Diamonds and Tambeu have replaced their former band's spastic weirdness with an emphasis on traditional structure and arrangement that showcases the breezy sounds of calypso, synth pop and rustic Americana. Although Sea lacks some of the Unicorns' surprises, its compelling and better-developed songs more than compensate, cementing Diamonds' status as a great pop songwriter.