Diane Morgan left her co-stars standing in Charlie Brooker’s Weekly Wipe, where she was the gormless pundit Philomena Cunk, and as Liz, the hatchet-faced single mum in Motherland. She was also quietly magnificent in Ricky Gervais’ After Life, where she played Kath, an elaborately coiffed ad saleswoman. A mordant stare from Morgan can do the work of 20 pages of script, so a show of her own has...