Viewers settling down to watch Frozen Planet II might have been expecting soothing scenes of nature after an emotional few days of news coverage, but were met with an episode that some said left them "sobbing" and "traumatised".
Sir David Attenborough's exploration of the Earth's coldest environments returned for a sequel 11 years after the original series, reminding viewers of the brutality of nature.
In one particularly difficult to watch scene during the debut of the BBC One series, a bear was hunting musk ox cubs who had become separated from their parents.
The newborn cubs were not yet old enough to distinguish a friendly grown up from a deadly predator, with disastrous results for some of them.
One viewer tweeted: "Hungover watching Frozen Planet and the little Bison calves were too young to tell the difference between friend or foe. Little dude went up to get a cuddle off a bear. I can't deal with this."
Another viewer agreed: "Well, I was enjoying Frozen Planet II until the bear went on a murdering spree. I must be feeling fragile. It was all a bit much."
Someone else wrote: "Put Frozen Planet on for 2 seconds to see a bear killing little calfs. Off it goes!! Can't watch that."
The mother of one of the ox cubs did eventually return and guide it to safety, but it didn't end so well for all of the young animals.
One person tweeted: "Needed David Attenborough Frozen Planet 2 for his soothing grandfatherly voice after 4 emotional days…but seeing a young cub find its mum and a polar bear turning serial killer broke me."
Many others agreed that they found the brutal scenes too tough to watch, with one person tweeting: "Those baby musk ox’s on frozen planet Jesus Christ what a rough watch that was."
Someone else wrote: "Traumatised watching this baby ox massacre."
Another upset viewer wrote: "I think it's safe to say that's the first time I've ever sobbed over a musk ox."
Someone else asked: "Anyone else watching frozen planet and is there a support group for people who watch frozen planet."
Elsewhere, the episode showed the effects of global warming on Greenland, where the film crew captured the moment that huge areas of a glacier collapsed into the sea, creating icebergs and adding to the rising sea levels.
One viewer tweeted: "Watched Frozen Planet 2 tonight. Absolutely wonderful programme. When will our governments waken up to the reality of global warning? Stop paying lipservice to ending fossil fuel production and actually do it. Wind and solar power is cheaper, quicker and will save our planet."
Watch: See the trailer for Frozen Planet II