Please be advised, the following episode contains scenes of an extremely graphic nature that may be distressing for some listeners.

You're listening to Unexplained with me, Richard McClane Smith.

Season 3, episode 12. The Square, part 2.

Although the disturbing, dear boss letter, as it will come to be known, was received at the Central News Agency on September 27th.

It is a further two days before it is passed on to the police, who swiftly dismiss it as a hoax.

Later that evening, back in the White Chapel District of East London,

PC Lewis Robinson is patrolling Aldgate High Street when he sees a crowd of people gathered around something on the ground.

Drawing near, he realises it is a woman sprawled out on the pavement, drunk.

PC Robinson pulls her up and implores her to stand, but as soon as he lets her go, she slumps against the wall and slides down slowly back to the ground.

Half an hour later, with the help of a colleague, Robinson takes the woman to Bishop's Gate Police Station and places her in a cell for the evening.

When they ask her name, she tells them only it is nothing.

Minutes later, she is fast asleep.

It has just gone midnight when station Jailer George Hutt hears the unknown woman singing softly from her cell.

When he checks on her, she asks to be released, but Hutt insists that she remain there until she is able to take care of herself.

Outside, a storm is brewing above the streets of White Chapel.

Shortly before 1am, as a heavy rain starts to fall, local resident Israel Schwarz turns into Burner Street just south of White Chapel Road.

Up ahead, he notices a couple standing outside the entranceway to Duckfield's Yard, overlooked by the International Working Men's Educational Club,

one of the pair is a man roughly five and a half feet tall, with dark hair and a small brown mustache, wearing a black felt hat with a wide brim.

He is standing in front of a woman, who he tries to pull into the street, but she resists.

Enraged, he throws her onto the pavement and she lets out three short screams.

Schwarz, who had seen the whole incident, responds by crossing the road and walking away.

Hearing the man calling out to someone on the other side of the road, Schwarz turns to find a second man is now following him.

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