The S Terror/The Great Detective's Daughter (Ｓな戦慄/名探偵の娘 Esu na Senritsu/Meitantei no Musume) is the tenth episode of Kamen Rider W. It is the concluding part of the 'S' arc, S standing for Sweets (Dopant) and Sonozaki (Family). It features the debut of the HardBoilder's Start Dash Mode.