Trip is injured and fated to die. Desperate to save him, Phlox and Archer agree to use one of Phlox's alien pets to create a clone of Trip to farm for transplant organs. The clone, named Sim, matures to adulthood in mere days, retaining Trip's memories but developing his own personality. Accepting his fate, Sim is sacrificed to save Trip, but not before expressing his (and possibly Trip's) feelings toward T'Pol.