Welcome to the documentary from the BBC World Service.

This is the fifth floor.

The fifth floor, you knowsson.

This is the fifth floor at Farnak Amidi Sobath. This is the fifth floor at the heart of global storytelling with BBC journalists from all around the world.

I'm your host, Faranak Amidi.

This is the story of family ties lost and found and of questions that remained unanswered for over half a century.

It all started with a boy, a soldier and a duffel bag.

The soldier hit the boy in Etula, as they say in Colombia, which is a type of big bag

that soldiers used to put their belongings in.

So he took the boy on the ship heading back to Colombia and kept him fed and watered

for 28 days at sea and would play cars with him to entertain him.

This is Jose Carlos Quetto from BBC Mundo.

He's a journalist based in Colombia,

and he's recently been working on the extraordinary story of the Tulo boy,

a mystery that gripped and moved Colombia for decades.

What is the story of a Korean child?

He was smuggled into Colombia.

And then the child grew up to be a man in Colombia,

became famous somehow and lived haunted by his past.

So who was this Korean boy?

And what happened to him?

To find out, we need to go back in time to the 1950s in what is now South Korea. American and Korean troops advanced through the city of

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