Doctor Who S10 Ep4 Knock Knock

WARNING: Embargoed for publication until 00:00:01 on 02/05/2017 - Programme Name: Doctor Who S10 - TX: 06/05/2017 - Episode: Knock Knock (No. 4) - Picture Shows: ***EMBARGOED UNTIL 00:01hrs 2nd MAY 2017*** The Doctor (PETER CAPALDI), Bill (PEARL MACKIE) - (C) BBC/BBC Worldwide - Photographer: Simon Ridgway