John Oliver used this week's Last Week Tonight to look at a very popular trend in entertainment: America's fascination with prisons. With shows like Orange Is the New Black taking off in a major way, you'd expect Americans would know a lot about our systems of incarceration. However, outside of programs like Sesame Street offering some Muppet-friendly facts, actual education about prison conditions is in limited supply.

So Oliver laid down some facts for his audience. One in every 100 adults in America is incarcerated, he noted, totaling over 2 million in prison or jail. Also a fact: Conditions in those prisons are inhumane and depressing.

Not knowing a prisoner or being one naturally means you'll know less about prison conditions, and that's understandable. Less understandable for Oliver: Director of Federal Prisons Charles E. Samuels, Jr. not being able to remember the size of a solitary confinement cell at a Senate subcommittee meeting. When Samuels finally did 'remember' the size – six feet by four feet – Oliver wasn't satisfied.

"One, that was clearly a guess," he said. "And two, six by four is barely an elevator. That is the length of a six-foot party sub by the length of the amount of that party sub that's left over the following day. Because no one wants party subs."

Also problematic about prisons: the food. Short supply is one problem, but then there's cases of maggots being found. As Oliver noted, "The only time when you are happy to hear the phrase 'maggots were found' is when you are a maggot whose family was lost at sea."

Other issues Oliver tackles in the clip above include health care, jokes about rape, education, and the issues that arise when prisons are run like businesses. It was enough to make him depressed. Luckily, he gets a little help from some Muppet friends at the end.

"It's a fact that needs to be spoken," Oliver and the Muppets sang. "America's prisons are broken."