In the early 1920s, Joe Mears was a prominent passenger boat operator on the River Thames. His garage at Richmond maintained the coaches that transported holiday-makers to the river, creating a need for suitable vessels to accommodate smaller parties. Consequently, in 1922 and 1923, he built two sister boats named Mutt and Jeff. These vessels were named after two internationally popular cartoon characters created by Bud Fisher, a journalist with the San Francisco Chronicle. Jeff was the shorter of the two, often portrayed as the character who lost in their encounters.

Both launches were small, open craft measuring under 40 feet and were the first of Mears' boats to be powered by internal combustion engines. Mutt operated on the route from Westminster to London Bridge, while Jeff ran from Westminster to Old Swan Pier. During the period when Joe Watson served as skipper and Bert Wheeler as engineer, a return trip on Jeff cost one shilling.

Both launches participated in the Dunkirk evacuation during World War II and survived the war, although Mutt no longer exists. After 23 years of service, Jeff was sold to Thames Launches. In 1952, Arthur Jacobs of Windsor acquired her and renamed her Windsor IV. She operated trips to Boveney Lock near Windsor. Following the scrapping of Windsor II, she assumed that name.

Subsequently, Whatford & Sons of Hampton Court became her owners. When their business was sold in 1981, Turks Launches took over the vessel as a spare boat. Jeff is notable among the Dunkirk ships still in operation for retaining much of her original appearance. A trip aboard her offers a vivid connection to the lively social atmosphere of the 1920s, the era in which she originally served.

Remarkably, some of the passengers she once entertained would later be rescued by her from the beach at La Panne during the 1940 Dunkirk evacuation, returning safely to England.

As of April 2018, Turks Launches remains the owner of Jeff.