- Sometime in 1991, I was with Fateh Singh, my tiger guru, and we were wondering what happened to a few of the tigers that we were watching.

We could no longer find them.

And Fateh Singh felt that they were missing and maybe they could have been poached.

And I said, "No, not possible.

Who would poach these incredibly beautiful animals?"

But then began our year of horror.

Poachers started to be caught with skins.

(tool twangs) It knocked Fateh Singh and me out.

We just couldn't believe that this was a possibility.

- [Reporter] The price of bones is soaring as tiger numbers plummet.

India's tigers are being murdered so the Chinese can turn their bones into folk cures for fevers and rheumatism.

- I think the population all over India is going down.

I think the primary reason for this is poaching and the bone trade to meet the Chinese demand for medicinal derivatives.

I think the tiger faces probable extinction in the next decade.

- Fateh Singh had no time for poachers.

If he found a poacher, he'd charge after him, take him to jail.

He believed that that was the only way Ranthambore would survive.

And he was beaten up himself.

He nearly died.

His driver jumped on his body to save him and took the beating.

This is a letter my tiger guru Fateh Singh wrote at that time.

"It is a massacre.

When the police chief showed me the skin, I could not control myself.

Tears were rolling down my cheeks.

It's heartbreaking, and sometimes I feel guilty that I taught them to have faith in human beings.

All the tigers were shot at point blank range, just innocently looking at the man with the gun."

I think both Fateh and I felt that over the years we'd worked very hard with the tigers, they'd lost their fear of man.

And they treated the poachers in the friendliest of ways, and they lost their lives.

Because by now we had learned to identify individuals by their stripes, we could say with certainty that 30 tigers, tigers that we knew, were gone.

Around the lakes, just 15 terrified tigers remained, and I was determined to do all I could to keep them alive.