Written by Davy Kane, the crime thriller will follow an early forensic murder investigation, set against the backdrop of the Blitz.
James Fleet (The Vicar of Dibley) and Emerald Fennell (Any Human Heart) will also star in the series, loosely based on the memoires of Molly Lefebure, secretary to the Home Office Pathologist and pioneer of modern forensics Keith Simpson during World War II.
Kennedy will play Dr Lennox Collins, a cutting-edge pathologist, while Fleet is cast as his superior Professor Henry Stephens, and Merchant will play Collins's secretary Molly.
Executive Producer Sally Woodward Gentle said: "With Geoffrey Sax (White Noise, Doctor Who) directing Davy Kane's witty and fast-paced script we hope to depict London in the Blitz as a city living life on the edge."
ITV's Director of Drama Laura Mackie added: "We're delighted to commission Murder on the Home Front to add to ITV's portfolio of new drama."
Murder on the Home Front is currently shooting and is produced by Christopher Hall (The Last Weekend, Hidden).
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