Puerto Rico is in the middle of a catastrophic $70 billion debt crisis — one that many Americans aren't even aware of. So to get people paying attention, Last Week Tonight's John Oliver had Hamilton creator Lin-Manuel Miranda, the son of Puerto Ricans, appear on the show to rap about it.

Here's a small taste of Miranda's show, which you should absolutely watch in full starting at the 19:15 mark:

Yeah, my family's from Puerto Rico, the tropical destination where you can spend your Washingtons the spot where you vacation. A commonwealth with not a lot of wealth and not quite nation, $70 billion topic of conversation. Hoping to God John Oliver's comical dissertation resonates with the Congress that got us in this situation, along with suicidal tax incentive declarations. Yeah, we'll pay your bonds first, close the hospitals, fuck the patients. This is an island, 100 miles across, a hurricane is coming, and we're running up a loss.

Puerto Rico's crisis is serious. The poverty rate in the territory is 45 percent. More than 80,000 people fled the island in 2014. The government has even shut down more than 150 schools in the past few years and dramatically hiked sales taxes to try to get some revenue.

The story of how Puerto Rico got to this point is complicated, rooted in legal quirks that come from the island being a US territory but not a state. Puerto Rico originally flourished with manufacturing jobs due to tax credits exclusive to the island — which were later rescinded by Congress, sending it into hard times. Then Puerto Rico tried to pay its bills by issuing municipal bonds, which, again, had special status (exemption from local, state, and federal taxes) thanks to action by Congress.

But since Puerto Rico's economy never really recovered despite attempts to attract rich people to the island (with, of course, tax breaks), it could never pay off the debt from those bonds. And due to another legal quirk in the territory, the government can't declare what's known as Chapter 9 bankruptcy.

"Which is huge," Oliver explained. "If you are massively in debt, and you can't declare bankruptcy, you are stuck. And this happened because of a tiny amendment to a law in 1984. And the crazy thing is no one can say why it was written." (Seriously, lawmakers and historical records have no clue as to why.)

It gets worse. Even with the Zika virus now reportedly heading to Puerto Rico, the debt crisis is leading many doctors to leave the island — as many as one a day. "That is an attrition rate rivaling that of Grey's Anatomy," Oliver joked. "How have so many of you died? You work in a hospital!"

So Puerto Rico has turned to Congress for help, leading to a bill that would give the territory more breathing room to negotiate with creditors. But with the bill stalled in Congress, the island is still in a lot of trouble — so Oliver brought Miranda on his show to try to help.

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