In the mid-1930s the New York Central retained industrial designer Henry Dreyfuss with an eye to developing its first streamliner. Dreyfuss's plans were approved but when the railroad's management saw the final price tag, they balked. A disappointed Dreyfuss, taking a train out of town, saw a group of old surplus commuter coaches sitting in the yards at Mott Haven and had an idea. Shortly thereafter, the Central began rebuilding a group of the old cars to Dreyfuss's designs, while Dreyfuss busied himself with planning every detail from the locomotive to the dining car china. A new, tight schedule was adopted which trimmed five stops and a full hour off the running time of the previous train on this route. The Mercury of 1936 was the result.

The Mercury would be an immediate and unqualified success, prompting the New York Central to enter the streamliner race at full throttle. In the 1940s Mercury service would be extended west from Detroit to Chicago, while in the 1950s the Cincinnati Mercury would provide service from Cleveland to Cincinnati. But the Mercury's greatest legacy was probably the green light given Dreyfuss to design one of the finest streamliners ever to grace the rails—the 20th Century Limited of 1938.