February 1970, CIA headquarters Langley, Virginia.

Larry Chin sits in a small room, wired up to a polygraph machine.

It's the first lie detector test he's ever taken.

He's nervous, and he's right to be.

For nearly two decades, he's been working for the FBIS,

a division of the CIA that translates publicly available information for analysis.

All that time, he's also been a spy for the People's Republic of China.

Now he's been offered a promotion that will make him even more useful to Beijing and increase his security clearance,

but only if he can defeat this polygraph.

The examiner frowns at his machine.

Sorry, I need to repeat that one.

Again, are you Larry Chin?

Yes.

The examiner frowns again before fiddling with the polygraph machine.

These damn things, needles playing up.

That should do it.

The test resumes.

Chin feels a knot in his stomach.

It's the pressure of trying to answer the questions correctly.

He can see the examiner watching the needles jitter over the paper.

Chin also watches it to distract himself. Up and down they go, skittish and erratic. The knot starts to

loosen. Have you had extramarital affairs? Chin is surprised by the query. He wonders if that's a

...