This is the New Yorker Radio Hour, and this is a special episode of our podcast devoted to new reporting by the New Yorker's Heidi Blake.

Not so long ago, Heidi got a tip that led her to investigate one of the most notorious crimes in modern British history.

Five members of a family had been brutally murdered

at a rural estate. Heidi's reporting put the official account of that case into question,

and it challenges the foundations of the UK legal system. That story is told in blood relatives,

a new series from our investigative podcast, In the Dark,

which won the Pulitzer Prize for audio this year. Here's how it begins.

The shoreline in this part of England is marshy and riddled with inlets and creeks.

It's a pretty desolate place.

This is the coast of Essex, just northeast of London,

but an entirely different landscape.

The tides seep in and out with eerie drama, flooding the mudflats.

On some mornings, mist rushes up suddenly, over the the marshes and forms a briny fog I'm kind

of driving in under smouldering gray cloud and just this expanse of bleak salt marshes of the

blackwater estuary and it feels so isolated heading inland from the Blackwater Estuary. And it feels so isolated.

Heading inland from the Blackwater Estuary, away from the fog and the sea,

I turned onto a rough dirt track, with tall hedges on one side and open green fields on the other.

I wound around the lane, turned down a gravel drive, and there it was.

Here's the farmhouse.

Big signs saying trespassers will be prosecuted.

I had arrived at White House Farm.

A place so infamous in Britain that I later learned,

...