Muriel Spark (1918-2006) is acclaimed as one of the most eminent Scottish novelists in the contemporary literature world, whose favorite novel is a tragedy named The Drivers Seat, in which Lise, the heroine, schemes a homicide to gain so-called freedom and self-realization. The root causes of Lises tragedy will be analyzed from the dimension of Sartres Existentialism, which will further inspire the mod people in terms of the true meaning of life and freedom of choice.