This long-promised collaboration between the Afghan Whigs’ Greg Dulli and the Screaming Trees’ Mark Lanegan finally came to fruition in 2008 as the Gutter Twins, a nod to both men’s notorious pasts. The two lead singers never step on each other’s form. Instead, Dulli imports the sleek, tremulous rhythms of the Whigs and his Twilight Singers while Lanegan often stops time with his patient, low, bluesy bark. Together, they’ve built a night underground where mellotrons and crazy-distorted guitars meet various kinds of odd percussion. The ghost of Tom Waits can be heard in “Seven Stories Underground.” Dulli’s love for ‘70s R&B and funk shades “Each to Each.” “All Misery / Flowers” walks at Lanegan’s slow, determined pace, while “God’s Children” amps up to Dulli’s showbiz flash. Spiritually, these two intuitively understand one another, with Lanegan’s natural introversion folding nicely into Dulli’s extroverted raves. This is a side-project that is sure to remain a well-esteemed cult item — and a worthy curiosity — for years to come.