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“Manhattan” Season 2, Episode 6: Tickling the Dragon’s Tail

Liza maps out the possible effects of a radiation accident at Los Alamos

As the Trinity test draws closer, the scientists of Manhattan become increasingly concerned about safety. In particular, they worry about the risky criticality experiments, known as “tickling the dragon’s tail,” they are conducting to determine the critical mass of fissile materials. One mistake could cause a nuclear chain reaction and expose them to lethal levels of radiation.

Frank Winter also fears that the people who built the bomb will have no say over how it is deployed. He learns that President Roosevelt’s Target Committee, which will decide where the atomic bomb is dropped, does not include any scientists as members. In real life, several scientists were members of the Target Committee, including J. Robert Oppenheimer, Hans Bethe, John von Neumann, and British physicist William G. Penney.

Helen Prins, who speaks to the scientists on Frank’s behalf, wins enthusiastic support as she demands safer working conditions: “We are the ones who are bringing this thing down off the blackboard and into the world, and we deserve better.” But her appeal falls flat when she brings up the Target Committee. “We have bigger problems here on the Hill,” another scientist says.

To placate the scientists, Charlie allows Fritz to appoint an expert to assess the health effects of radiation on the Hill – none other than Liza Winter. But first she needs authorization from Colonel Darrow. “Do you know what happens in Building E?” she asks him.

“Something above your clearance,” he responds.

“Well, that wouldn’t stop it from killing me if it went fast critical and I was sitting in your chair.”

Liza gets her clearance, and Darrow orders the criticality experiments moved off-site.

Frank circulates a petition to the President in the Tech Area, calling for scientific representation on the Target Committee. This document may be based on Leo Szilard’s July 1945 petition, where a group of scientists argued that the U.S. should not use atomic bombs against Japan “unless the terms which will be imposed upon Japan have been made public in detail and Japan knowing these terms has refused to surrender.” As we have seen in previous episodes, Frank’s character is inspired by the brilliant – and mercurial – Szilard.

When Frank learns that President Roosevelt’s science advisor, Vannevar Bush, will be visiting the Hill, he asks Helen to hand Bush his petition. Jim Meeks considers signing, but his Soviet handler, Nora, warns him not to. “You don’t sign anything. You don’t stand for anything. You need to earn Charlie Isaacs’s trust. That is your role. Stick to the script.”

Charlie reports the petition to Darrow, but the colonel gives his permission for it to be distributed. “Let Dr. Winter run [this] up the flagpole. We’ll see who salutes.” After Charlie leaves, Darrow picks up the phone and calls FBI Director J. Edgar Hoover.

Meanwhile, Abby turns to the Bible as she seeks an explanation for her miscarriage. Charlie has none of it. “This is a fairytale. It’s a bedtime story. Things don’t happen for a reason. They just happen.”

At work, Abby discovers Paul is transmitting information from Oak Ridge to the British. After she confronts him, he lies and tells her that Charlie has resumed his affair with Helen, to throw her off balance. He claims he wants “revenge” against Helen, who has wronged them both, but Abby reports him to Colonel Darrow.

Unlike Charlie, the devout Darrow connects with Abby over the loss of her child. “Of course there’s a reason,” he tells her. “Pain is His voice, reminding you that you’re alive and at His mercy.” He kneels on the floor of his office and prays, and Abby, uncertainly, joins him.

Meanwhile, to punish Frank, Charlie assigns him to tickle the dragon’s tail. The ghost of Avram Fischer, whose car has just been discovered at the bottom of a pond, then appears to Frank. As Frank builds a stack of tungsten carbide bricks around a plutonium core, bringing the core closer to criticality, Fischer goads him into realizing why Darrow let the petition go forward. “The best blacklists, Frank, are the ones the traitors sign all by themselves.”

Realizing he needs to get back to the Hill to prevent the other scientists from running afoul of the FBI, Frank deliberately brings the reaction almost to criticality. A radiation alarm sounds. Soldiers rush him back to Los Alamos to be treated for radiation exposure, but he escapes from the hospital.

In a climatic speech, Frank urges the scientists to come with him to confront Bush. As the scientists march out of the Tech Area (Jim noticeably hangs back), an aide whispers something in Darrow’s ear. The colonel walks over to the American flag and lowers it to half-staff. President Roosevelt has died. The decision over the bomb will now be in President Harry Truman’s hands.

Safety was an important concern for Manhattan Project leaders. The project imposed strict safety measures in production facilities, and created a medical and health section to study the effects of radiation on workers. During and especially after the war, the Los Alamos Laboratory made important advances in radiation detection technology, including developing special radiation detectors to monitor internal exposure to radioisotopes.

Despite the numerous dangers encountered by Manhattan Project workers and scientists, the project, which employed approximately 600,000 people between 1942 and 1947, had surprisingly few accidents. As historian Alex Wellerstein notes, “At Oak Ridge and Hanford, they claimed an exceptional occupational safety record — their injury rates were (they claimed) 62% below those of private industry.” Wellerstein records 24 fatal accidents at Los Alamos between 1943 and 1946. Most of these tragedies were related to construction; only four involved scientists.

Nevertheless, as the show captures, “tickling the dragon’s tail” was particularly dangerous, although the two fatal accidents associated with it occurred after the end of the war. Frank’s experiment with the bricks resembles the one that scientist Harry Daghlian was conducting when he accidentally received a fatal dose of radiation on August 21, 1945. Less than a year later, scientist Louis Slotin was also exposed to lethal amounts of radiation when experimenting with the same plutonium core as Daghlian. Wellerstein has a fascinating account of the so-called “demon core,” which was the third plutonium core cast at Los Alamos (the first was used for the Trinity test, the second for the Nagasaki bomb).

Physicist Lawrence Litz helped cast the third core, which was hurriedly prepared in the event that a third atomic bomb was needed against Japan. In a 2012 interview, Litz remembered that the casting took “about twenty-four hours, and we had to work straight through.” He recalled, “Of course we were worried about it [radiation] but that was the job to be done. We always tried to be safe.”

Despite this concern for safety, the urgency of the war effort did lead scientists to take risks. “People in the laboratory, who were doing experimental work, often took risks that nobody would accept, except under the pressure of a war,” recalled scientist Murray Peshkin. “After all, other young men like us were in trenches in France. They did experiments that today would be considered insanely dangerous.”

Will the scientists get a voice on the Target Committee? How will Colonel Darrow react to Fischer’s death and Paul’s espionage? What will Liza learn in her research? We will post our next recap next week!