Toprak posed as an inspector and accompanied the Seventh Doctor to the home of Mathilde Vignes, hoping to determine if Mathilde had stolen cheese cultures from her sister, Victoire Vignes. However, Toprak was actually working for the Voltranons, who hoped to use the bacteria from the cheese cultures to wipe out most life on Earth. Only a few thousand people, including Toprak, would be taken away to the Voltranon homeworld.
Toprak was stopped by the Doctor, Chris Cwej and Victoire. (PROSE: Culture War)