French electroclash artists may be a dime a dozen, but who else save the deceptively innovative four-piece responsible for 2005’s seductive Witching Hour would deliver not one but two cuts sung entirely in Bulgarian? Even more welcome than vocalist Mira Aroyo’s lingual leveraging, however, is the happy revelation that the fourth effort from the veritable League of Musical Nations surpasses even its breakout predecessor.

Having previously ventured into poppier, more accessible territory, other artists might be tempted to move in an ever-more-mainstream direction. But Ladytron breaks out the heavy machinery and digs deep, testing and teasing with synths and sequencers until something cold, dark and glistening is unearthed.

The rhythms of more intense tracks like “Ghosts,” “I’m Not Scared” and “The Lovers” are staggeringly dense yet refrain from becoming ponderous, while the juxtaposition of seemingly innocuous vocals with lyrics like Helen Marnie’s “I set myself on fire without you” (“Burning Up”) and Aroyo’s “A pocketful of doubts/A night of fading stars and a legacy of clouds/Obliterate the Sunday” (“Season of Illusions”) adds significant heft to metaphors that might otherwise come across as more trite than junior-high poetry. And like the rawest of emotions inherent in those otherwise-forgotten times, the lasting imprint never quite fades.

The bottom line: ***1/2