CBS captured the first Thursday of April in key demo categories behind a strong return for “The Big Bang Theory” after a couple of weeks off and good scores for “The Millers” and “Two and a Half Men.” ABC was strong closing the night with “Grey’s Anatomy” and “Scandal,” though the latter cooled a bit.

Of note in latenight was a surge for CBS’ “late show with David letterman,” whose 3.2 household rating in nielsen’s overnights was its best on any night since 2012. It beat both NBC’s ‘Tonight Show’ and abc’s. ‘Jimmy Kimmel Live,’ which tied with a 2.4.

According to preliminary national estimates from Nielsen, CBS rolled early in primetime with “The Big Bang Theory” (4.8 rating/17 share in adults 18-49, 17.4 million viewers overall), which was back after taking two weeks off during the net’s coverage of the men’s college basketball tournament and was in line with its last original. It was followed by “The Millers” (2.9/9 in 18-49, 11.4 million viewers overall), which shot up by about 20% over its prior firstrun episode, and “Two and a Half Men” (2.5/7 in 18-49, 9.4 million viewers overall) and “The Crazy Ones” (1.8/5 in 18-49, 6.5 million viewers overall), both of which were up a tenth. “Elementary” closed out the night (1.6/5 in 18-49, 7.8 million viewers overall), down a tenth from its most recent fresh episode.

At ABC, the finale of “Once Upon a Time in Wonderland” (0.9/3 in 18-49, 3.2 million viewers overall) was followed by “Grey’s Anatomy” (2.6/7 in 18-49, 8.0 million viewers overall) and “Scandal” (2.8/9 in 18-49, 8.0 million viewers overall). The 9-11 p.m. dramas led their time periods in demos, though “Scandal” came down from last week’s above-average 3.1 demo rating.

Fox opened with “Hell’s Kitchen” (1.7/6 in 18-49, 4.9 million viewers overall), followed by “American Idol” (1.8/5 in 18-49, 7.7 million viewers overall) and “Surviving Jack” (1.2/3 in 18-49, 4.5 million viewers overall). “Idol” appears to have hit another low, down a tenth from last week, while the new comedy held up pretty well by retaining about 90% of its premiere’s young-adult rating.

At NBC, “Community” (0.9/3 in 18-49, 2.6 million viewers overall) and “Parks and Recreation” (1.1/4 in 18-49, 2.7 million viewers overall) returned, with the former at a low-water mark and the latter down a tick from its prior original. The comedies were followed by an original “Hollywood Game Night” (1.1/3 in 18-49, 2.7 million viewers overall), which matched its top demo score since Feb. 27, and “Parenthood” (1.2/4 in 18-49, 3.7 million viewers overall). Like “Scandal,” “Parenthood” was down from its above-average score of last week and may have lost some viewers to “Elementary,” which was airing for the first time in three weeks.

CW aired repeats of “The Vampire Diaries” (0.3/1 in 18-49, 0.9 million viewers overall) and “Reign” (0.3/1 in 18-49, 0.9 million viewers overall).

Preliminary 18-49 averages for the night: CBS, 2.5/8; ABC, 2.1/6; Fox, 1.6/5; NBC, 1.1/3; CW, 0.3/1.

In total viewers: CBS, 10.0 million; ABC, 6.7 million; Fox, 5.5 million; NBC, 3.2 million; CW, 0.9 million.