Edward James Olmos Cmdr. William Adama Actor Mary McDonnell President Laura Roslin Actor Katee Sackhoff Lt. Kara "Starbuck" Thrace Actor Jamie Bamber Capt. Lee "Apollo" Adama Actor James Callis Dr. Gaius Baltar Actor Tricia Helfer Number Six Actor Grace Park Lt. Sharon "Boomer" Valerii Actor Michael Hogan Col. Saul Tigh Actor Aaron Douglas Chief Galen Tyrol Actor Tahmoh Penikett Lt. Karl "Helo" Agathon Guest Star Kandyse McClure Officer Anastasia Dualla Guest Star Paul Campbell Billy Keikeya Guest Star Alessandro Juliani Lt. Felix Gaeta Guest Star Sam Witwer Crashdown Guest Star Alonso Oyarzun Socinus Guest Star Nicki Clyne Cally Guest Star Michael Rymer Director Ronald D. Moore Writer