Well, one thing is for sure: Cable news viewers like films about killer whales a lot more than ones about pro-nuclear power. CNN’s airing last night of the documentary Pandora’s Promise delivered a wet 345,000 total viewers in its 9-11 PM time slot and just 145,000 among adults 25-54. The heavily promoted Robert Stone-directed film was way, way down from the 1.36 million that CNN Films’ Blackfish drew in total viewers in the same slot two weeks beforehand. Promise also got less overall viewers than the film about keeping killer whales in captivity at marine theme parks pulled in just the key demo. Winning the time slot over CNN’s cable news rivals, Blackfish had 472,000 among the 25-54s when it aired October 24. CNN Films acquired the nuke-themed Pandora’s Promise in April this year after it screened at the Sundance Film Festival and had a theatrical run. Such docus as Promise and Blackfish are a part of the network’s attempt to broaden its programming scope — though with mixed results, obviously.

Related: CNN Falls To Lowest Daily Primetime In Over A Year

The fallout of Promise’s low ratings Thursday night was that the Jeff Zucker-run CNN once again was far behind both Fox News Channel (2.54 million total viewers and 400,000 in the demo) and MSNBC (810,000 and 229,000) in both categories during the two-hour slot. CNN also was down 43% in overall viewers and 24% among the 25-54s year to date and 41% and 21%, respectively, for October averages. Results that can’t bode well for a cable network that just came off its lowest primetime week in over a year and the worst since Zucker took over in January. Once the ratings for this week come in next week, there could be a whole other type of meltdown.

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