Does the Mallory case fit a pattern that you're seeing coming from Chinese intelligence?

Yes. We currently have three pending cases against former intelligence officers, and they're alleged to have been spying on behalf of the Chinese.

It's hard to overstate how unusual it is to have three cases like this ongoing.

It's not unusual. It's unprecedented.

Kevin Mallory was a former clandestine case officer for the CIA, who the Justice Department believes was recruited by a Chinese spy.

Did you send them anything on that phone?

I send them some tests.

Tonight, 60 Minutes gets an insider's view at what espionage looks like.

Malta sits as a sun-dappled speck in the Mediterranean,

a short ferry ride to Sicily and not much farther to Libya.

Over the last three millennia, Malta has been conquered or colonized by just about every world power.

Most of the 500,000 people here are Catholic, a tradition that started early.

The Apostle Paul is said to have been shipwrecked here in 60 AD.

But as you'll see, today the proud Maltese are dealing with accusations that are far from holy.

You fly up alongside that wolf and you shoot a tranquilizing dart into it.

Five minutes it goes down.

We process the wolves.

We take blood and we attach a radio collar.

And then we follow them for their life, hopefully.

Yellowstone wolves are fierce and territorial.

The leading cause of death is attacks from other wolves.

And their look is uncontrollable.

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