Roslin’s abduction by the Cylon hybrid triggers a power struggle in the Colonial fleet.

Read the summary of the episode at the Battlestar Wiki

Notes from the BSG chronology

This episode takes place concurrently with the next episode, "The Hub".

Didja Know?

The title of this episode, Sine Qua Non, is a Latin phrase meaning "without which not," generally used to mean a given event cannot happen without first some preceding condition.

The opening titles show the fleet at a population of 39,674, up one from the previous episode "Guess What's Coming to Dinner?" without explanation. Presumably, a birth occurred in the fleet.

Characters appearing or mentioned in this episode

Natalie Faust (dies in this episode)

Dr. Cottle

Jacob Cantrell

President Roslin

Tom Zarek

Apollo

Admiral Adama

James McManus (reporter who interviews Zarek on wireless, voice only)

Dee

Colonel Tigh

Tory Foster

Baltar

Athena

Hera

D'Anna Biers

Starbuck

Romo Lampkin

Lance (Lampkin's cat, in Lampkin's imagination only, deceased)

Caprica Six

Ellen Tigh (in Colonel Tigh's visions only)

Racetrack

Skulls

Gonzo (corpse only)

Chief Laird (mentioned only)

Sandman (mentioned only, deceased)

Captain Doyle Franks (mentioned only)

Phantom (mentioned only)

Joseph Adama (mentioned only, deceased)

Faye (Lampkin's wife, mentioned only, deceased)

Jennifer (Lampkin's daughter, mentioned only, deceased)

Katie (Lampkin's daughter, mentioned only, deceased)

Jake (dog)

Didja Notice?

Due to the absconding of the rebel baseship with President Roslin aboard, Vice President Tom Zarek becomes President of the fleet for a brief time in this episode.

The Six-model Cylon called Natalie Faust dies in this episode. As she lays dying in sickbay, she begins to utter the Prayer to the Cloud of Unknowing, as we learned from Athena that Cylons do when they fear they are about to die without resurrection in "A Measure of Salvation". She does not resurrect in a new Six body as the fleet is too far away from a Resurrection Ship.

Zarek remarks that the post-Colonial government has been in existence for the past 5 years, but it has really only been about 3.5 years in the timeline.

Notice that Lampkin has many radio (i.e. "wireless") units in his quarters. Why is that? Does he listen to broadcast sources from all across the fleet simultaneously to keep abreast of what is happening?

Lampkin tells Apollo he'll take the case for finding a suitable interim president to replace Zarek pro bono. Pro bono is a shortened version of pro bono publico, a Latin phrase meaning "for the public good", and usually also means the task is done without fee.

Racetrack discovers Gonzo's corpse in a Raptor that has leapt back to the fleet after the disappearance of the rebel baseship. Gonzo's moment of death is depicted in the following episode, "The Hub".

Aboard Gonzo's Raptor, Admiral Adama finds the now-scorched copy of the book Searider Falcon he gave to Roslin in "Escape Velocity".

This episode implies that Peter Laird has been made deck chief after the demotion of Tyrol by Adama in "Escape Velocity".

At 18:05 on the Blu-ray, Lance's meow is heard from inside Lampkin's duffle bag even though we learn later in the episode that the cat was killed long before by protesters against Lampkin for his defense of Baltar that started in "The Son Also Rises".

The song Athena hums to herself in the brig (and later to Hera) is the same tune that Boomer hummed as she inspected a Cylon Raider captured by the Galactica in "Flesh and Bone".

Dr. Cottle discovers that the captive Caprica Six is pregnant, seemingly by Colonel Tigh during his "interrogations". If the baby were to come to fruition, it would be the first fully-Cylon baby; sadly, the pregnancy ends in a miscarriage in "Deadlock".

Adama and Starbuck mention a Raptor pilot called Phantom. This is the pilot's only mention in the series.

Lampkin remarks to Adama how Adama had given Apollo a lighter which had belonged to his grandfather (Joseph Adama). This occurred in "The Hand of God".

At 30:48 on the Blu-ray...damn, Lampkin has worse handwriting than me!

At 31:20 on the Blu-ray, a copy of Law & Mind: The Psychology of Legal Practice by Joseph Adama, Apollo's grandfather, is seen under Lampkin's bed.

At 31:40 on the Blu-ray, notice that Lampkin carries away the duffle bag he uses to house Lance when he travels away from his quarters...despite not being shown loading the cat into it. This is an early indication that the (living) cat is a figment of his imagination, as revealed later in the episode.

After determining that Apollo is only the potential candidate who fulfills all the needs of an interim president, Lampkin pulls a gun on him, threatening to prevent Apollo's ascent to the office. The gun is a COP 357 Derringer (referred to as a Stallion by Tyrol in "Home" Part 2).

Apollo becomes president of the fleet at the end of this episode (though Laura Roslin resumes the presidency when she returns in "Revelations").

Admiral Adama gives up his command position (temporarily) to Colonel Tigh in order to stay behind in space to wait for the reappearance of the rebel baseship and his beloved Roslin. He hands his admiral's collar insignia over to Tigh. This may explain why Tigh is seen wearing admiral's insignia pins in the earlier episode "Escape Velocity"...the scene there was inserted from a scene originally for this episode (my theory anyway).

Now Acting President, Apollo gives Lampkin custody of Jake, dog hero of the New Caprica resistance. Jake previously appeared in third season episodes set on New Caprica, but the dog seen here, though similarly colored, is a different breed from the one seen in those earlier episodes.

At 42:33 on the Blu-ray, the belt strap buckle Adama wears in the Raptor as he waits for Roslin to return in the rebel baseship has an RCI logo on it. RCI is Racer's Choice Inc., a manufacturer of safety products and accessories for race cars.

Admiral Adama identifies himself by his old callsign Husker in the Raptor, perhaps because he has, for the moment, relinquished his admiral's rank to Tigh.