What is the best Maggie Smith role of all time?

Tea with Mussolini

A 1999 Franco Zeffirelli film where Smith plays Lady Hester Random, a formidable expatriate Englishwoman living in Fascist Florence.

Gosford Park

A 2001 Robert Altman murder mystery where Smith plays Lady Constance Trentham, the acerbic, cash-strapped aristocrat who provides some of the film's sharpest wit.