Lucy: Later in 1928, Agatha's divorce finally became official.

The next week, Archie married Nancy Neele.

It must have felt like yet another public humiliation.

Agatha was adrift.

Her daughter was off at boarding school, she had no ties, no husband, and more notoriety than she wanted.

But there was at least the freedom to get away.

In November 1928, Agatha threw caution to the wind and booked herself a second class ticket on the famous Orient Express.

She'd once travelled the world with Archie by her side.

Here was her chance to go solo.

And this was her first stop-- Sirecki Station, Istanbul.

Agatha liked to tell the story about how fate brought her here.

She had planned to go to the West Indies.

But then at a party, she ran into a couple who'd just come back from Iraq.

They told her how marvellous it was.

They told her about these incredible train journeys.

The next day, she changed her ticket, and five days later she was off.

So in the autumn of 1928, Agatha arrived here in Istanbul ready to begin the next stage of her journey even further east.