It has been painful to watch once-treasured New York rap duo Mobb Deep become a tawdry, self-implosive caricature. The makeover began in 2005, when Prodigy and Havoc were lured under 50 Cent's G-Unit umbrella with promises of Ferraris and huge album sales. They got the whips they were promised, but Mobb Deep's Blood Money fell so short of critical and commercial expectations that G-Unit barely deigned to promote the thing. The intervening years have not spared the duo heartbreak. Prodigy's reward for an ace solo album (Return of the Mac, released in 2007) was more than three years in prison. While Havoc remains an industrious producer for hire, he long ago lost his critic's-darling status to imitators like Madlib and Alchemist. Mobb Deep is nothing if not cavalier, though. Prodigy has staked out a prolific and eccentric presence on Twitter — he's gotten noticeably well-acquainted with caps lock. His recent verses sound as though they were recorded from the pulpit of a prison-chapel sermon, which is to say they're as intense as Mobb's 1996 classic Hell on Earth. Even if the duo can't manage another "Shook Ones" or "Quiet Storm," their next album should slather on the fire and brimstone thick.