In the 1940s she appeared on-stage in an Agatha Christie play, "Appointment with Death", which was seen by Christie who wrote in a note to her, "I hope one day you will play my dear Miss Marple". From 1963 to 1966 she played Mrs. Peace, housekeeper to Reverend Stephen Young (played by Donald Sinden) in the highly rated TV series "Our Man at St. Mark's". Hickson played the housekeeper in the Marple film "Murder, She Said" in 1961 (based on Agatha Christie's original novel "4.50 From Paddington"), which starred Margaret Rutherford as Miss Marple. From 1970 to 1971, she played Mrs Pugsley in "Bachelor Father". Hickson played Mrs Chambers in "Whatever Happened to the Likely Lads?" In 1986, she played the part of Mrs. Trellis in "Clockwise".