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What time is Catching a Killer: a Knock at the Door on TV?

A devastating documentary that paints a portrait of a British Chinese family torn apart by violence, and the police hunt to catch the killers

Published: Monday, 14th May 2018 at 5:34 pm

At 6pm on 31st January 2017, three days after Chinese New Year, the lives of one family were changed irrevocably when 64-year-old Hang Yin Leung heard a knock at the front door and opened it.


Eleven days later, she had died following a brutal attack.

The episode is part of a gripping series, Catching a Killer, which follows the police as they investigate murders and search for missing people.

Here's everything you need to know about Catching a Killer: A Knock at the Door.

When is Catching a Killer: A Knock at the Door on TV?

Catching a Killer: A knock at the door will air on Monday 14th May at 9pm on Channel 4.

What's it about?

Home alone, Hang Yin Leung hears a knock at the door of her family home - her husband, with whom she runs a takeaway business, is at work. The house is ransacked by six men, but the worse is yet to come as Hang Yin is later hospitalised and admits to the police the nature of the brutal attack.

Eleven days after hearing that first knock on the door, Hang Yin died from the injuries she sustained. The police struggle to piece together a case, but with two weeks having passed they are unable to rely on forensics.

The episode, filmed over the course of 12 months, grants the viewer extraordinary access to the police as they tackle one of “the most difficult homicides” they have ever faced, pouring over CCTV evidence, waiting to uncover a clue or mistake made by one of the murderers.


The episode also focuses on the Leungs, migrants from Hong Kong who travelled to the UK in search of a better life for their son.

Mr Leung (Channel 4)
Mr Leung (Channel 4)

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