Sometimes documenting nature can be be just as brutal as nature itself. That's what a BBC film crew learned when faced with a choice between doing their jobs and helping a trapped group of penguins who had been left to die.
For documentary filmmakers there is an unwritten rule to never interfere, especially when it comes to nature. No matter how hard it may be to watch, they are only there to observe.
A BBC crew filming Emperor penguins in Antarctica faced a particularly tough moral dilemma when a group of mothers and their chicks became trapped in a ravine, unable to scale the icy walls to reach the warmth and safety of their colony.
To help the penguins the crew would have to break the oldest rule in the documentarian's book, but if they didn't intervene the penguins and their chicks would be left to die in subarctic temperatures as low as minus 76 degrees Fahrenheit.
Eventually the crew decided that they just couldn't stand by and watch.
On Sunday viewers tuned in to catch the latest episode of BBC Earth's Dynasties from world renowned naturalist Sir David Attenborough.
Many were expecting the episode on Emperor penguins to be a relaxing and breathtaking look at the lives of the adorably pudgy birds. What they didn't expect was a lesson in just how unforgiving the Arctic climate can be.
After more than a dozen mother penguins and their chicks became trapped in a ravine viewers found themselves caught in a story of a life or death struggle.
Viewers watched as several of the mother penguins attempted to scale their way up the icy slopes of the ravine, but with their chicks in tow many of the mothers weren't able to make the climb and fell back to the bottom.
One mother penguin made the heartbreaking choice to save herself and leave her chick behind as she climbed out of the ravine.
It was more than some viewers could handle.
If the story didn't have a happy ending, it might have been too much for some viewers, but luckily the film crew obviously felt the same while watching the trapped penguins fight for their lives. In an unprecedented move, the crew decided to intervene and do what they could to save the penguins.
To help the penguins the crew dug out a stepped ramp leading out of the ravine and back to their colony.
"'We opted to intervene passively," said Will Lawson, the show's director. "Once we'd dug that little ramp, which took very little time, we left it to the birds. We were elated when they decided to use it."
"No interference policy" be damned. Viewers were overjoyed that crew broke the rule to step in and help the penguins.
The penguins' story was an emotional roller coaster, but one that was well worth it, thanks to the crew that not only captured it but gave it a happy ending.