It is 1930 and in the quaint Queen Anne village of Tilling (which is by, but not quite on, the sea) all seems as quiet as a mill pond. But its eccentric inhabitants exist in a world seething with gossip, faddishness and petty one-upmanship. From her centrally located house, Mallards, Miss Elizabeth Mapp reigns supreme over them all. Until, that is, the arrival of Mrs Emmeline 'Lucia' Lucas. With her passion for music, art and high culture of all kinds, Lucia is quite an addition to Tilling's social scene. It's not long before Mapp is indulging in all kinds of foul plots to undermine her accomplished tenant.