'Pretty Little Liars' Season Finale Draws Impressive Ratings

Pretty Little Liars Season 2 Finale Still - H 2012

Pretty Little Liars big season two finale hit ratings gold for ABC Family.

The reveal of the mysterious "A" attracted 3.7 million viewers to the buzzy teen drama, based on the Sara Shepard novels. Monday's episode was the franchise's second most-watched, behind only "Moments Later" that aired in January 2011 during season one.

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Compared to the penultimate episode of the season, the Liars finale gained 1.2 million viewers (3.7 million vs. 2.5 million). It was on par with the season-three opener in June and the first-season finale in March 2011.

Liars posted series highs among key demographics: adults 18-34 (1.6 million), adults 18-49 (2 million) and women 18-49 (1.7 million). In the younger female category, women 18-34 (1.3 million), the finale was ABC Family's top telecast.

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On broadcast, Liars was up against the first hour of ABC's Dancing With the Stars premiere, Fox's House, CBS' How I Met Your Mother/2 Broke Girls and the first hour of NBC's The Voice.

According to ABC Family, the Liars finale produced nearly 645,000 tweets on Twitter while the episode aired. At one point during the hour, the show averaged 32,000 tweets per minute.

Pretty Little Liars returns in June for season three.