They began their own collaboration in 1991. The brothers have often made pieces with plastic models or fibreglass mannequins of people. An early piece consisted of eighty-three scenes of torture and disfigurement derivative of those recorded by Francisco Goya in his series of etchings, "The Disasters of War" (a work they later returned to) rendered into small three-dimensional plastic models. One of these was later turned into a life-size work, "Great Deeds Against the Dead", shown along with "Zygotic Acceleration, Biogenetic, De-Sublimated Libidinal Model (Enlarged x 1000)" at the "Sensation" exhibition in 1997.