In June 2007 Lance was working as the head of human resources at H.C. Clements, where Donna had just landed a temp job. His offer of a cup of coffee quickly turned into a romantic relationship, at least for Donna, who pressured him into marriage. Their wedding was scheduled for 24 December 2007. In truth, Lance hated Donna and regarded her as one of the most stupid and irritating people he had ever met.
Unbeknownst to Donna, Lance had been working for the Empress of the Racnoss for at least six months. At the Empress' behest, he dosed her with dangerous Huon particles over this period, intending for his Huon-saturated bride to provide the energy that the Empress needed to resurrect her race.
When the Doctor became involved, Lance feigned ignorance until they came face-to-face with the Empress. He then revealed that he had been working with the spidery alien all along in exchange for being taken away from Earth to see the stars. The Doctor and Donna would escape, however, forcing the Empress to resort to making a new "key" to unlock the Secret Heart, and so she force-fed Lance her Huon solution.
The Empress would re-capture Donna and she would find herself next to her treacherous fiancé entangled in the Empress' web. In order to awaken the hibernating Racnoss within the Earth, the Empress dropped Lance down the shaft. The fall likely killed him and then the Racnoss would have fed upon his corpse.