It may be involved in an upcoming update, or its development and release may have been cancelled entirely.
Duke of Bridgelum was a scrapped random event that involved going to ScapeRune to help the Duke of Bridgelum reassemble dead cows from their component parts. The player would have to select certain cow parts (udders, hind legs, etc.) from an interface.
The random event was scrapped because the testers at the time pointed out that the dismembered cow parts looked grotesque. The reward would have been pieces of a cow outfit, which exists in Old School RuneScape.