The Bentley S1 was the first evolution of the Bentley S-Series. Introduced in 1955, the S1 was powered by a 4.9L inline six engine and available in hardtop or open top versions. A top of the line performance variant known as the S1 Continental was also offered during the course of S1 production, which lasted until 1959. The S1 was replaced by the Bentley S2.