Sine Qua Non

S04E08·8.0·May 30, 2008·1h·Syfy

President Roslin's abduction by the Cylon Hybrid triggers a bitter power struggle within the Colonial Fleet.

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#16In Season 4of 20 rated episodes

#52All-timeof 73 rated episodes

−0.5vs season avgSeason 4 averages 8.5

2008First airedMay 30, 2008

Guest stars

Donnelly Rhodesas Dr. Cottle

Rekha Sharmaas Tory Foster

Kate Vernonas Ellen Tigh

Leah Cairnsas Lt. Margaret "Racetrack" Edmondson

Alexandra Thomasas Hera Agathon

Judith Maxieas Picon Delegate

Andrew McIlroyas Jacob Cantrell

Iris Palulyas Speaking Delegate Dahlia

Donna Soaresas Gemenon Delegate

Ryan McDonellas Lt. Eammon "Gonzo" Pike

Rod HardyDirector