I love Maggie Smith, and obviously she didn't mind taking roles in a number of Agatha Christie dramas. Nowadays most kids see her as Professor McGonagall from the mediocre Harry Potter series and nothing else. Similar to Alec Guiness being remembered for Obi Wan in Star Wars, their true talent and range as thespians are demonstrated by their extensive body of work through the years.
In "Death on the Nile", Dame Maggie Smith was joined by Mia Farrow, Bette Davis, David Niven, and Angela Lansbury, starring Peter Ustinov (who would also later be typecast for his marvellous performance as Poirot).
Broken up into parts below, click on numbers.
Now don't get me wrong, I'm an advocate of owning the legit dvds (since I own all of these)... However I also like sharing classics, so if you love them, they're all pretty cheap to purchase and of far better quality.
Death on the Nile Part 1 (I don't know why but part 1 isn't the proper link and there is no trace of the correct link) 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 (2 -12 are fine)
Need more? Other films...
Gosford Park? You'll have to rent this one :) trailer here