Welcome to The Inquiry, on Charmaine Cozier. Each week, one question, four experts, and an answer.

A man suddenly falls seriously and violently ill during an internal flight from Siberia to Moscow in August 2020.

The plane diverts for an emergency landing, an ambulance meets it on the runway.

In hospital, he's placed in a coma and put on a ventilator.

This isn't a normal medical emergency. The sick passenger is President Putin's most prominent critic, Alexei Navalny.

He's been poisoned with novichok, a chemical nerve agent first developed by the Soviet Union in the 1970s,

and his supporters suspect the president is behind the attack.

Two days later, the opposition leader is flown unconscious from Russia for intensive care in Germany.

He defies the odds and survives the assassination attempt.

You might think that he wouldn't be keen on returning to the state that all the evidence suggests tried to kill him, but you'd be wrong.

He returned to Russia in January of this year, but moments after he landed, he's arrested and imprisoned.

He'll now likely spend years in a prison cell.

So this week we're asking, why did Alexei Navalny return to Russia?

Part one, back from the dead.

He is very much a guy next door, an ordinary person, with extraordinary life.

I'm Arkady Astrovsky, I'm the Russia and Istnie Europe Editor, the economist and I'm the author of a book called The Invention of Russia from Gorbachev's Freedom.

To Putin's War.

Arkady first met Alexei Navalny 12 years ago, he's interviewed him many times.

He is a politician through and through, I mean he is a professional politician.

Driven, I think, by his clear desire for power, because he wants to change the world.

In terms of personality, he is very unassuming in many ways.

There is no grandeur about him.

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