<p>Colin Firth and Matthew Macfadyen have credited Michelle Ashford's script for their unique chemistry in Second World War thriller Operation Mincemeat.</p><p>Firth plays naval intelligence officer Ewen Montagu in the film, alongside Macfadyen as grounded flight lieutenant Charles Cholmondeley.</p><p>Operation Mincemeat is in UK cinemas from 15 April.</p>
