Number Four

Simon is a Humano-Cylon agent who pretends to be a doctor caring for Starbuck after her capture in "The Farm". He tries to casually persuade her into bearing children but is unsuccessful. When his diplomatic efforts fail he begins to operate on her, first harvesting her eggs then on orders from Six, attempting to surgically remove her ovaries. Starbuck realises he is a Cylon, kills him, and escapes from the Farm.

Another copy of Simon was briefly seen in "The Farm", a more well-kempt copy in a dark business suit who addresses Starbuck after the first copy's death. He is also killed by the resistance movement when they stormed the Farm to liberate her.

Simon was the first new humano-cylon model revealed since the Mini-Series, and brought the total number of known agents to 5.