Morven Christie (The A Word) and Vicky McClure (This is England) front The Replacement, a new psychological thriller for BBC One, written and directed by Joe Ahearne (The Secret of Crickley Hall, Doctor Who, This Life), produced by by Left Bank Pictures.

The series will also star Richard Rankin, Dougray Scott, Neve McIntosh, Navin Chowdhry and Siobhan Redmond.

When Ellen (Christie), a successful architect in her mid-thirties, falls pregnant, she finds maternity cover in Paula (McClure): brilliant, enthusiastic and raring to go. Ellen wants to champion her, but something’s not right. Ellen begins to fear for her safety when she suspects her replacement has a disturbing agenda. Can her suspicions be explained away as female rivalry and her own insecurity of opting out of work at the top of her game… or do they speak to something deeper?

This chilling mini-series examines the darker side of working women, motherhood and the issues that arise from making “the right choice”.

Morven Christie said: “Joe’s scripts are full of tension and it’s a genuine thrill to be given the opportunity not only to play this deliciously rich character, but to do so in my home-town, with this extraordinary cast. I feel so honoured to be part of this wonderful team, bringing these complex and compelling script to life.”

Vicky MClure added: “Joe Ahearne has written an incredibly complex and thrilling script. I’m really excited to play a role that is miles apart from previous characters. Looking forward to working with Morven and spending time in Glasgow.”

The 3 x 60’ series is produced by Nicole Cauverien and executive produced by Andy Harries and Suzanne Mackie for Left Bank Pictures and Matthew Read for BBC One.