“Ebola was not the exception. Ebola is a precedent.”

This warning, featured in a searing documentary from PBS’ Frontline that airs Tuesday nationwide, comes from Dr. Bruce Aylward of the World Health Organization, who was at the center of troubled efforts to curb the Ebola outbreak in West Africa.

The episode, like many aired by the award-winning journalism program, is at once infuriating, frightening and mobilizing. It should also be required viewing for anyone who wants to know more about the outbreak than panicked panels of pundits on CNN, or ambulance chases from airports in Western nations where a handful of health workers were treated.

The documentary sounds the alarm: The world was not prepared to deal with a disease that crossed borders and spread rapidly. More outbreaks like this one will occur as new diseases emerge from an increasingly crowded and resource-constrained world, especially one in which people are encroaching into previously wild habitat.

That provides ideal conditions for so-called zoonotic diseases to jump from species to species.

The hour-long episode is a damning indictment of everyone who failed to save lives when they had the chance. The government ministers in Guinea, Sierra Leone and Liberia are blamed, as well as the bumbling bureaucracy of the U.N.’s World Health Organization (WHO). None of them saw the onslaught before it was right on top of them.

Ultimately, the outbreak killed at least 10,892 people, according to the latest tally (though the documentary notes the actual tally is likely far higher). The episode does not waste time rehashing what we already knew about the disease, and puts the focus on putting a human face on those who suffered the most.

Filmmaker and journalist Dan Edge spent four months in West Africa, retracing Ebola’s steps back to a single tree at the remote Meliandu village in Guinea. That’s where it is thought that bats — a suspected disease reservoir for Ebola and other pathogens — first transmitted the disease to humans in December of 2014, well before anyone at the CDC in Atlanta or the WHO in Geneva heard about the outbreak.

In an interview with Mashable, Edge says one key lesson that emerged from his team’s reporting is that the disease surveillance in West Africa, and indeed much of the developing world, is “woefully inadequate.”

In the case of Ebola, the outbreak “was not identified as an Ebola outbreak for nearly four months,” he said. “The world is not set up in such a way to deal with cross-border epidemics.”

One key piece of evidence that the documentary details: The role that a small American company, Metabiota of San Francisco, played in advising the Sierra Leonean government in how to respond to the building crisis.

The company already had a presence in the country researching tropical diseases. By its own admission, the company had no experience dealing with Ebola. Still, the government listened to its input rather than humanitarian groups on the front lines, like Doctors Without Borders, which had extensive experience handling Ebola cases and was sounding the alarm to anyone who would listen that the outbreak was way out of control and spreading fast.

Interestingly, Metabiota staff published a peer reviewed study on April 20 in PLOS Currents Outbreaks on Ebola’s emergence in Sierra Leone. The study makes no mention of the company’s role in advising the government on the proper response to contain the outbreak.

“Healthcare systems must be immediately alerted and communication through regional networks must be enacted in a manner that permits quick adaptation to the rapidly evolving situation,” the study, published April 20, says about a successful Ebola intervention program.

Perhaps no organization emerges from this episode more bruised than the WHO, which is headquartered in Geneva.

Evans says it was obvious that the WHO, which exists to aid governments in responding to public health threats, was “impotent” in the face of the outbreak — but this was partly by design. “They had no army of medics ready to deploy,” he said. “They’re not a clinical organization.”

That should change, Evans says: “Now is the time, the small window of opportunity when the horror of the outbreak is still very fresh in our minds.”

The WHO announced reforms late last month that would address some of the shortcomings. But Evans is not optimistic they’ll be acted upon.

While filming in remote Guinea, where deforestation and mining is encroaching on more formerly wild territory, Evans says was aware of how quickly he could have traveled to the capital, then hopped a flight to London or Paris or New York.

“The world is connected in a way that it never has been before,” he said. “There is no such thing as a far-away place anymore.”