The series is set during the period 1903–1930 and takes place largely in the London town house of the Bellamy family. The "upstairs" and "downstairs" of the title refers to, respectively, the Bellamys and their servants. The first season introduced David Langton as Richard Bellamy, Rachel Gurney as his wife, Marjorie, Nicola Pagett as their daughter, Elizabeth, and Simon Williams as their son, James. The household servants were Gordon Jackson as Angus Hudson (the butler), Angela Baddeley as Mrs Bridges (the cook), Jean Marsh as Rose Buck (the head maid), Pauline Collins as Sarah Moffat (maid), Patsy Smart as Maude Roberts (Lady Marjorie Bellamy’s personal maid), Christopher Beeny as Edward (first servant), and George Innes as Alfred (the footman). In the second series Jenny Tomasin was introduced as Ruby (a kitchen/scullery maid) and George Innes was replaced by John Alderton as Thomas Watkins. Alderton and Pauline Collins later played their characters in a spin-off series, "Thomas and Sarah".