On the heels of a strong series premiere, USA Network’s The Sinner, from Universal Cable Productions, is up in key demos in its second week, making it cable’s No. 1 new series in P18-49, P25-54 and total viewers.

The August 9 episode of The Sinner starring Jessica Biel and Bill Pullman, was up 7% to 1.4 million in adults 18-49, up 5% (to 1.6 million) in adults 25-54 and up 4% (to 543,000) in adults 18-34 in Live+3. Over its first two episodes, the series is averaging 3.5M P2+.

The Sinner follows a young mother, Cora (Biel) who, when out with her husband (Christopher Abbott) and son, commits a startling act of violence and, to her horror, has no idea why. Detective Ambrose (Pullman) finds himself obsessed with uncovering the woman’s buried motive, which launches an inverted and utterly surprising crime thriller whose driving force is not the “who” or the “what” — but the “why.”

Episode 3 debuts Wednesday at 10/9c.