DC’s Legends of Tomorrow on Thursday night premiered to 3.2 million total viewers and a 1.2 rating (per finals), giving The CW its best demo number in the time slot in exactly two years (Vampire Diaries‘ 100th episode).

Legends doubled predecessor Vampire Diaries‘ season-to-date average (1.3 mil/0.6) and bested TVD‘s year-ago numbers in the time slot (1.6 mil/0.8). TVLine readers gave the series debut an average grade of “B+.”

For those who may wonder of the spinoff’s sires: The Flash this season is averaging 3.6 mil/1.4, Arrow 2.7 mil/1.0.

Leading out of Legends, Season 3 of The 100 opened to 1.9 mil and a 0.7, a sharp increase over The Originals‘ season-to-date average in the time slot (1 mil/0.4) and besting its own Season 2 average (1.5 mil/0.5). It was The 100‘s highest-rated outing since the second episode of Season 1; TVLine readers gave it an average grade of “A-.”

All told, The CW enjoyed its most watched Thursday in more than three years (since 10/11/12) and its highest rated Thursday in more than two years (since 11/21/13).

Elsewhere in the ratings….

NBC | The Heroes Reborn (3.8 mil/1.0, average grade “B-“) finale matched series lows, The Blacklist (7.4 mil/1.6) was steady and Shades of Blue (6.9 mil/1.4) rose a tenth.

CBS | Leading out of an old Bang (11 mil/2.2), Life in Pieces (8.8 mil/2.0) and Mom (8.5 mil/1.7) were steady, while Angel From Hell (7 mil/1.4) ticked up. Elementary (6.3 mil/1.1) was flat.

FOX | American Idol (9.4 mil/2.4) was up 8 percent and two tenths week-to-week.

ABC | Beyond the Tank (4.3 mil/1.0) and the Diet show (2.3 mil/0.6) were flat.

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