The new drama ranks as ABC's lowest-rated scripted debut to date, while "Grey's Anatomy" hits a series low and leaves room for a steady "Scandal" to finally eclipse its veteran lead-in.

Plenty of viewers had other plans Thursday night, with TV usage among adults 18-49 predictably off during the Valentine's holiday. The demo audience was down the most between 8 and 9 p.m. (7 percent from last week), recouping a little over the rest of primetime.

CBS and The Big Bang Theory (5.4 adults) won the night, though the comedy was off from last week's 6.2 adults rating by eight-tenths of a point. Two and a Half Men (3.8 adults) was off by three-tenths, with Person of Interest (3.0 adults) only down by one-tenth and Elementary even with last week's 2.2 rating in the demo. The network averaged a dominant 3.3 rating with adults 18-49 and 13.8 million viewers.

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American Idol (3.6 adults) suffered from the 8 p.m. usage drop, losing half of a point from last week's Thursday outing. Glee (1.7 adults) also fell by half of a point, giving the network an average 2.7 adults rating and 8.8 million viewers for the night.

Zero Hour got off to an inauspicious start on ABC. Averaging a 1.3 rating with adults 18-49 and losing viewers and some of the demo in its second half-hour, the drama opened 41 percent south of Last Resort's premiere in the time slot in September. It stands as ABC's lowest-rated in-season premiere for a scripted series. Grey's Anatomy (2.7 adults) was down four-tenths of a point from last week to a series low, leaving room for Scandal to grow from its lead-in with a steady 2.8 adults rating. The network averaged a 2.3 adults rating and 7.6 million viewers.

Community (1.1 adults) fell sharply from last week's season four premiere, losing eight-tenths of a point and hitting a series low. Parks and Recreation (1.5 adults) lost half a point, and an hourlong episode of The Office (2.0 adults) was off a tenth of a point from last week's half-hour outing. A Law & Order: SVU repeat at 10 p.m. eclipsed both episodes of Do No Harm in the time slot with a 1.0 adults rating. NBC averaged a 1.5 in the demo and 3.5 million viewers.

The Vampire Diaries (1.0 adults) was off by a tenth of a point from last week, as was Beauty and the Beast (0.5 adults). The CW averaged a 0.8 rating with 18-49-ers and 1.9 million viewers.

Univision averaged a 1.5 rating in the demo and 3.7 million viewers.