Ripper Street episode 4 airs, Sunday 20 January at 9pm on BBC One.

The brutal clearing of a local slum for the underground railway reveals an almost indecipherable murder scene and an unreliable slum girl witness.

Lucy Eames (Emma Rigby), beautiful and disturbed, is the unlikely key to a byzantine web of conspiracy that appears to entangle progressive London councillor Stanley Bone (Paul McGann), Long Susan and the benevolent Dr Karl Crabbe (Anton Lesser) of the Lark Rise asylum. As Reid closes in on the killer, it becomes clear that the condemned slum is home to dark secrets that someone is desperate to protect.

Check out the picture gallery below…

© BBC/Tiger Aspect