If you knew Lily Allen only from the British tabloids, it’d be easy to mistake her for just another vapid celebrity. Abandoning the reggae lilt of her debut in favor of a luminous pop sound, this terrific second album sets the record straight. An acid-tongued moralist disguised as a careless pleasure seeker, she casts a scathing eye on substance abuse in “Everyone’s at It” and gleefully skewers bigots in “Fuck You,” occasionally pausing for a surprisingly tender love song. Amazingly, Allen rarely comes off as heavy handed. Her exuberance makes these blunt diatribes feel like good fun.