The second-season debut of CBS’ Under The Dome was the top program Monday night in total viewers (9.39 million) and in the demo (2.2 rating) – beating its nearest competitor in overall audience (ABC’s The Bachelorette) by more than 3 million viewers, and, Fox’s MasterChef by 19% in the demo. CBS boasted it’s the summer’s most-watched and highest-rated scripted program to date.

But, Under The Dome fell 33% from last summer’s debut in the demo, and 21% from last summer’s finale —  landing just one tenth from its series low of 2.1/6. CBS counters that Under The Dome’s premiere season was one of the most time-shifted program across all platforms, adding nearly 4 million viewers across the first season’s 13 episodes.

Fox took the night in the demo (1.7/5 to CBS’s 1.6/5) with MasterChef (1.9/7, 5.2 million viewers) and 24: Live Another Day (1.5/4, 5.76 million viewers). MasterChef  was up 12% in the demo compared to last week, to hit its highest rating so far this season. 24: LAD climbed 7% in the demo and 100,000 viewers.

At 8 PM, NBC’s infomercial Harry Potter: The Making Of Diagon Alley (0.8/3, 3.0 million viewers) tied for No. 2 in its time period among broadcasters with men 18-34. After that, NBC’s American Ninja Warrior repeat (1.4/4, 4.5 million viewers) retained 82% of last week’s rating for an original in the demo, and 87% of last week’s overall crowd for a first run (4.467 million vs. 5.151 million).

ABC’s 8-10 PM The Bachelorette continued to rank No. 1 in its 2-hour time period with total viewers (6.3 million), adults 18-34 (tie) and all key women demos.  The Bachelorette inched up 3% week-to-week in overall audience and held steady in the demo. At 10 PM, against CBS’ Dome launch, ABC’s Mistresses was up week-to-week in total viewers  (14%) and adults 18-49 (10%) to deliver best-since-premiere numbers on both counts.