The Leader (or commonly referred to by the Visitors as "Our Great Leader") is the head of a military dictatorship that controls the Sirian (Visitor) population on Sirius 4 and controls every resource and ship-of-the-line in the entire Sirian Fleet through his ministers. The Leader was constantly mentioned, but not seen, in the series.
Early in the Leader's military career, he was regarded as a military genius and quickly rose through the ranks, then the Visitors suffered a massive defeat in an interplanetary war with an un-named alien superpower that resulted in the destruction of several Visitor colony worlds. This was the only defeat he ever suffered and he vowed he would have his vengeance. He then left the military and joined the political sector of their society.
His rise to power began when Sirius 4 experienced several extreme environmental and economic disasters (natural and visitor-made) which left the planet critically short of food and water. He constantly blamed the weakness of their civilian leaders for lack of relief in the crisis and for their defeats in the war the Visitors were engaged in and used the populations' frustration at their current leaders to expand his powerbase. When the environmental and economic problems became critical, the Leader launched his coup and overthrew the original republic-based government and replaced it with a more military-favourable one.
With the entire military at his command; he began his war of revenge on the un-named power, but his resources began to dwindle. His science officers discovered the planet Earth 8.7 light years away, which contained an abundance of resources. He planned to steal every drop of water (leaving the planet a wasteland) and humans themselves for food and cannon fodder in the war. He sent a total of 50 Motherships, led by Supreme Commander John and his personal envoy Diana, to conquer and complete the mission.
The Leader was "most disturbed" by the defeat of the military force sent to Earth following the Red Dust's deployment, but with so few remaining resources left in his war machine he knew Earth was too valuable to abandon and he authorised Fleet Security Officer Lydia to lead another fleet back to Earth to recommence harvesting operations. He decided to keep a close watch on the invasion's progress, and sent several key military figures to Earth to assist in the invasion. This resulted in Charles' death and Inspector General Philip's defection to the Fifth Column (he remained unaware of the latter).
The Leader finally had enough of the constant stalemate and decided to personally come to Earth and lead the Final Invasion. To do so, he declared an Armistice with the Resistance and recalled all soldiers from the Earth's surface. Then he lured the Resistance leaders to the LA Mothership and attempted to convince the Starchild, Elizabeth Maxwell, to help him find the Anyx, an artifact hidden on Earth that could have the power to destroy either the human species or the Visitor species completely. These efforts failed and she escaped, along with the Resistance, back to Earth and on the trail of the Anyx. However, the Armistice he enforced was a ruse to destroy the Resistance groups around the world and leave it open for occupation. This succeeded with catastrophic results.
Behind the ScenesEdit
It is also notable that in the original miniseries, the Final Battle, and The Series, the Leader is often referred to as a man. The comic issue Meanwhile Out In Space also states that he has a son who is the Prince of the Visitors. However, in The Second Generation, it is revealed that The Leader is a woman.