Throwing Muses have long thrived on unannounced transitions, such as the woozy turn from propulsive rock to diffuse synthesiser on 1996's “Shark.” They still surprise in the 21st century: 2003's “Pretty or Not” swings between vulnerable and volcanic, while “Slippershell” balances acoustic starkness with gurgling saturation. And Bob Mould adds another new element with halting guest vocals on "Dio."