Ratings: Scandal, Elementary and Blacklist Slip; Grey's, Odd Couple and Bang Rise; American Crime Tops Hour

ABC’s American Crime debuted on Thursday night to 8.4 million total viewers and a 2.0 demo rating, down from both How to Get Away With Murder‘s debut (14.1 mil/3.8) and its week-ago finale (9 mil/2.8), yet improving upon Black Box‘s spring 2014 launch in the time slot (6.9 mil/1.5).

Despite dropping 12 and 33 percent of its lead-in, the freshman drama — which TVLine readers gave an average grade of “B+” — easily led the 10 o’clock hour in both total viewers and in the demo.

Opening ABC’s night, Grey’s Anatomy (8.1 mil/2.4) rose 7 percent and two tenths. Scandal (9.6 mil/3.0) slipped three tenths.

Elsewhere….

FOX | American Idol (9.3 mil/2.1) ticked down a tenth week-to-week; Backstrom (3.9 mil/1.0) gained a tenth.

NBC | The Slap (3.4 mil/0.8) dipped in viewers but inched up a tenth in the demo. The Blacklist (8 mil/1.7) slipped two tenths, matching its series low. (That said, NBC notes that the drama has improved the time slot by 175 percent versus the previous season average.) Allegiance (3.4 mil/0.8) was flat.

CBS | The Big Bang Theory (17.9 mil/4.7) and The Odd Couple (12.5 mil/3.0) each added viewers and two tenths in the demo. Mom (9.6 mil/2.2) ticked up a tenth, Elementary (7.5 mil/1.3) slipped 10 percent and two tenths.

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