Assassin's Creed Syndicate Episode 5: Michel Reuge's Vault

The Secrets of London are collection of music boxes scattered throughout London by the Assassin Michel Reuge; inside the music boxes were discs, marked with the Assassin insignia, that acted as keys for Reuge's Vault, in which he presumably hid a Piece of Eden.
Jacob and Evie helped Alexander Graham Bell recover the cables he had ordered for his independent telegraph line.