Blancpain's connection to the ocean is indeed iconic, and the Fifty Fathoms stands as a legendary timepiece in the history of diving watches. Introduced in the early 1950s, it was one of the first modern dive watches designed to meet the rigorous demands of professional divers and military personnel. The collaboration between Jean-Jacques Fiechter, Blancpain's CEO at the time, and Bob Maloubier and Claude Riffaud, founders of the French Combat Swimmers Corps, was pivotal. Their combined expertise—Fiechter's passion for diving and the military's operational needs—resulted in a watch that set the standard for dive watches.

Key innovations included:
- Water resistance: The Fifty Fathoms was named after its ability to withstand depths of 50 fathoms (approximately 91 meters), which was considered the maximum safe depth for divers at the time.
- Rotating bezel: A unidirectional bezel allowed divers to track their dive time safely.
- Legibility: The watch featured a clean, luminous dial for visibility underwater.
- Automatic movement: This reduced the risk of water entering the case through a manual winding crown.

The story of this particular Fifty Fathoms is as remarkable as the watch itself. In the summer of 1957, Mr. Matthouse, an avid diver, was on a trip to the South of France when he met a fellow diver at the Club Alpin Sous-Marin. Noticing that Mr Matthouse wasn’t wearing a diving watch, the man offered him his own Blancpain Fifty Fathoms at an exclusive "factory" price. Surprised and intrigued, Mr Matthouse asked how that was possible. The man simply replied, "I make them." That man turned out to be none other than Jean-Jacques Fiechter, Blancpain’s former CEO and the visionary behind the Fifty Fathoms. This particular watch, accompanied by photographs, diving logs, service records, and other documentation from Mr. Matthouse, is more than just a timepiece—it’s a piece of history. Adding to its significance, the watch was serviced by Blancpain’s Atelier Vintage in 2016.