Door and Richard share a glass of 40,000-year-old wine from Atlantis with the Angel Islington. He tells them that the only way to find out who killed Door's family is to deliver a vital key to him. But the key is in the custody of the machine-gun-carrying Black Friars.
click here to see where to watch or (watch here).
Ready to Watch Neverwhere, Season 1, Episode 4?