At a distance of 115 million light-years, a narrow ribbon of stars named Oyashio has been drawn from a dissolving globular cluster beside an ultra-diffuse galaxy—the first such stellar stream ever detected beyond the Milky Way. Discovered almost by chance in archival Hubble imagery and confirmed by a second telescope, it reminds us that the universe quietly archives its own history in structures we have not yet learned to read. The stream's slender width encodes the invisible gravitational architecture of its host galaxy, offering astronomers a new way to weigh the dark matter that shapes gala