Kunal Nayyar and Simon Helberg

The Big Bang Theory really is bigger than ever.

The CBS hit surged to an all-time high audience of 17.4 million viewers and a season-high 5.5 in the adults 18-to-49 demographic Thursday. That boosted lead-outs Two and a Half Men (13.9 million, 4.1) and Person of Interest (14.5 million, 3.1) to season highs in their respective demos. Elementary (10.7 million, 2.3) was up a tenth.

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On the other end, The Office (4.1 million, 2.0) fell four-tenths to tie a series low. The rest of NBC's lineup was steady.

Fox's The X Factor (7.3 million, 2.4) was up a tenth, while Glee (5.3 million, 2.1) dropped three-tenths.

On ABC, Last Resort (5.8 million, 1.3) tied a season low. Grey's Anatomy (8.6 million, 3.1) was also down, but Scandal (6.1 million, 2.1) rose two-tenths.

8 p.m.
CBS:
The Big Bang Theory 17.4 million (5.5); Two and a Half Men 13.9 million (4.1)
ABC: Last Resort 5.8 million (1.3)
Fox: The X Factor 7.3 million (2.4)
NBC: 30 Rock 3.4 million (1.2); Up All Night 3.1 million (1.3)
CW: The Vampire Diaries 2.8 million (1.2)

9 p.m.
CBS:
Person of Interest 14.5 million (3.1)
ABC: Grey's Anatomy 8.6 million (3.1)
Fox: Glee 5.3 million (2.1)
NBC: The Office 4.1 million (2.0); Parks and Recreation 3.6 million (1.7)
CW: Beauty and the Beast 1.6 million (0.6)

10 p.m.
CBS:
Elementary 10.7 million (2.3)
ABC: Scandal 6.1 million (2.1)
NBC: Rock Center with Brian Williams 4 million (1.1)