text: sometimes a great notion ( battlestar galactica ) " sometimes a great notion " is the thirteenth episode in the fourth season of the reimagined battlestar galactica . it aired on television on sci fi and space in the united states and canada respectively on january 16 , 2009 and on sky one in the united kingdom on january 20 , 2009 . this episode is the first after the mid - season finale of the fourth season ( " revelations " ) , which aired on june 2008 . the episode title is a reference to the novel of the same name , written by ken kesey . the episode was also the last to be written before the 2007 – 2008 writers guild of america strike . it received a nielsen rating of 1 . 6 and was received positively throughout . the episode continues from " revelations " , where both the colonial fleet and the rebel cylons finally found earth , only to find it devastated by a nuclear holocaust at least 2 , 000 years before , and the discovery leads to despair all across the fleet . the episode was not given an opening title sequence , but the survivor count for the episode was 39 , 651 . plot both the human fleet and the rebel cylons are disillusioned after finding earth devastated by a nuclear holocaust , which occurred at least 2 , 000 years prior to the events of the episode . after research on the bodies found in the soil , the cylons and dr. baltar ( james callis ) conclude the remains are not human , but cylon in origin . the rebel cylons further state the mechanical cylon remains resemble older centurions of theirs , but are of a kind unknown to them . following this , they postulate that the thirteenth tribe consisted of a different kind of cylon which existed over 2 , 000 years ago and moved out from to populate earth . when addressing the fleet , admiral adama ( edward james olmos ) never states this fact , leaving the fleet in the belief that the thirteenth tribe was human . meanwhile , samuel anders ( michael trucco ) , galen tyrol ( aaron douglas ) and tory foster ( rekha sharma ) receive memories of their lives on earth 2 , 000 years ago . kara thrace ( katee sackhoff ) has leoben ( callum keith rennie ) help track the origins of the beacon . however , what they find is a crashed colonial viper , containing a corpse with starbuck 's dog tags . after kara recites what the hybrid has told her , leoben becomes scared and retreats , with thrace wondering what she is . in shock , thrace takes the body and burns it on a pyre , and decides to not tell anyone about what she found , making people believe she lost the signal . in the fleet , president roslin ( mary mcdonnell ) burns her book of pythia , and is unable to address the fleet because of feeling that she led the fleet nowhere , and believing the prophecy is a lost cause . lee adama ( jamie bamber ) and anastasia dualla ( kandyse mcclure ) revisit their relationship , and after their evening together , dualla returns to her quarters , and commits suicide . devastated by this , admiral adama acquires a handgun from a marine and attempts to coerce tigh ( michael hogan ) into killing him , which fails . adama breaks down relieved and converses with tigh about past memories , and tigh reminding adama of his duties as commander of the fleet . adama eventually steps back into the cic , and makes an announcement that he will find a home for the fleet , gives instructions to search for any nearby habitable star systems , and invites their new cylon allies to join them . as the fleet prepares to leave earth , d 'anna ( lucy lawless ) , devastated by the knowledge that history repeats itself endlessly , decides to remain on earth to die , rather than being hunted by cavil . tigh walks into the sea and receives a flashback of his life on earth ; he realizes that his wife , ellen ( kate vernon ) , is the last of the final five cylons . in the vision , a dying ellen tells tigh that " everything is in place " and that they will be " reborn , again , together " . they are then destroyed in this vision by a nuclear blast . production writing this episode was written back - to - back with the season 4 . 0 episode , " revelations . " according to co - writer david weddle , the title of episode was chosen as co - writers david weddle and bradley thompson outlined their story for the producers . the title is taken from the ken kesey novel , sometimes a great notion . the book is one of weddle 's favorites . while writing the novel , kesey made notes in which he urged himself to make the novel 's protagonist quit living , and this became the theme of this episode as well . weddle stated that he and the other writers were inspired by the idea of taking a strong , heroic character and piling misfortunes on him or her until finally the character breaks : what happens in that moment ? does he despair ? does he get up and go on ? for me , there is no more defining moment for a character . we tried to do this with almost all the characters in this episode : [ adama ] , laura , kara , lee . we ripped everything out from under them then sat back to see what they would do . what were their individual breaking points ? and if they did break , would they stay broken or grope toward a recovery ? the " fox in the river " story told by admiral adama comes from the novel , and also from real - life incidents with wildlife swimming out to sea near weddle 's home in malibu , california . the decision to have lt. dualla commit suicide in this episode was made after the writing staff felt there had to be fallout from discovering that earth was a nuclear ruin . moore explained : there had to be a cost . there had to be a price somebody paid for that discovery . not everybody could take that . not everyone could just say , " ok , that didn 't work out , let 's go on to next week 's episode . " it felt like somebody would just say , " no , i 'm done . i just want to find a little moment of time where i can feel good about myself one last time , then i 'm finished with this long nightmare . " and that seemed like that would be dualla . dualla fit this best because she had lost two men whom she loved , and all she had left was the hope of finding earth . moore also came up with the idea that dualla 's suicide was actually an act of hope and control , not despair . although the network had concerns that the script was too depressing , moore successfully defended the writing by saying that it might be the last episode of the series and that viewers who had stuck with the show for three and a half seasons would not be put off by yet another " dark " episode . writers weddle and thompson considered giving the characters some leeway in interpreting what they had found . among the options debated were giving the fleet some hope that earth might be some other planet , allowing a character to discover a new part of the prophecy of pythia , giving one of the characters a vision of an earth - like planet , and placing a clue in the ruins that would direct the fleet to yet another planet . all were rejected . weddle and thompson also worked extensively on the scene in which admiral adama tries to provoke col. tigh into killing him . moore encouraged weddle and thompson to give the adama character progressively crueler lines . the writers were the ones who inserted the line in the script in which adama mentions ellen tigh 's sexual infidelity . on the set , however , actor edward james olmos changed the line from adama saying ellen wanted a man with " real blood in his veins " to " main vein , " then ad - libbed the line in which the character said , " i could smell her . " the scenes where dualla finds the set of jacks and where laura roslin holds the plant cutting were added by director michael nankin . weddle notes that although nankin usually peppers his writers with script notes , he did not do so for this script . cost estimates indicated that the script , as originally written , would be $ 300 , 000 over budget ( about two - and - a - half times what the studio would have permitted ) and a number of scenes were cut . an extensive opening segment which would have depicted the destruction of earth was changed to the filmed segment in which tyrol sees a flash of light and his shadow is left on a wall . however , nankin restored the scene in which helo , dualla , adama and roslin ride back to galactica in the raptor . the fifth cylon according to showrunner ronald d. moore , the concept of ellen and saul tigh 's relationship being more than an average husband - and - wife relationship went back to the pilot mini - series for battlestar galactica but was not made part of the story arc for the two characters until the middle of season 3 . as writing progressed on the episode " torn , " the writing staff needed to explain why baltar would not see all 12 cylon models aboard the base star . moore came up with the concept of five cylon models that had yet to be revealed . later , during writing sessions for the episode " rapture , " d 'anna has a vision in which she confronts the final five cylons in the opera house , and apologizes to one of them . although moore and the writing team had yet to formally settle on ellen tigh as one of the final five , moore says it was his intention for the cylon to be ellen . when one of the final four cylons was revealed to be saul tigh in the episode " crossroads , " moore finally decided to make ellen the fifth cylon because " tigh being revealed as a cylon was such a profound shift in that character , such a big leap for the show , that it felt really natural that she was also a cylon . " a clue to the final cylon 's identity was inserted into several episodes , when col. tigh sees ellen 's face on the number six model . moore 's decision was revealed to the writing team at series writers ' conference which occurred between season 3 and season 4 . other characters were considered as the final cylon model , but the writing staff agreed none had the same resonance as ellen tigh . the decision to reveal ellen tigh 's true identity in " sometimes a great notion " was made because moore did not want season 4 . 5 to devolve into a guessing game about who the final cylon might be , and because he wanted the final episode of the series to be about issues other than who the final cylon was . writers ' strike the script for " sometimes a great notion " was the only script finished by the time the 2007 – 2008 writers guild of america strike began . revised script pages were turned in the day before the strike . moore decided that the crew should proceed as if shooting would be green - lit , and flew to vancouver , british columbia , to speak to the cast and crew before the strike began . the strike proved so vexing that the studio did not give approval for shooting to occur until the night before it was to begin . the cast and crew were very emotional during filming , as they were concerned that this might be the last episode ever filmed and the series cancelled if the strike was a lengthy one . olmos helped to work up the cast 's emotions for the shoot by telling everyone that the show was ending . according to co - writer weddle , olmos repeatedly told the cast , " this is the end , i think we all feel that . they 're not going to bring the show back . they 'll pull the sets down . we 'll never shoot another episode . " actress kandyse mcclure improvised the lullaby her character hums before committing suicide , and series composer bear mccreary used the melody for part of the episode 's musical soundtrack . filming the producers intended for this episode to be the last to star lucy lawless , who portrayed number three . they only had lawless for one day during the filming of the episode . most of the earth scenes were shot on and around centennial beach , in , british columbia . two days before the shoot much of the location set was destroyed by a rain storm with 90 kilometres per hour ( 56 mph ) winds , but the art department crew repaired it in time for the shoot to occur on schedule . the final shots for the episode " revelations " were filmed in the three hours immediately preceding the shooting of the beach scenes for " sometimes a great notion . " director michael rymer , who helmed " revelations , " and nankin agreed that all earth sequences should be reminiscent of the work of film director ingmar bergman , so wide camera lenses were used , the color was desaturated , and long rather than short takes were used . the scene in which adama goads tigh was scheduled to last a day . originally the segment was to be shot in small bits and flashbacks edited between each line , but the scene was instead shot as one long take . actors olmos and michael hogan struggled for several hours to find the right emotional tone . moore said that the audience should accept the irradiated planet as earth . " they have found earth . this is the earth that the 13th colony discovered , they christened it earth . they found earth . " reception " sometimes a great notion " was seen by 2 . 1 million total viewers in the u.s , earning the episode a 1 . 6 household rating . this included 1 . 3 million adults age 18 - to - 49 ( the show 's target demographic ) , and 1 . 4 million adults age 25 - to - 54 . the episode was the top cable program in the 10 p.m. slot among men age 18 - to - 49 and men age 25 - to - 54 the night it premiered . the ratings for the episode increased 23 percent over the season 4 . 0 average in household ratings and total viewers , increased 21 percent over the same period for adults age 18 - to - 49 , and increased 15 percent over the same period for adults age 25 - to - 54 . according to nielsen live - plus - seven - day ratings data , an additional 0 . 7 million viewers watched the episode via time - shifted digital video recorder , a 32 percent increase over the day - of - delivery airing . time - shifted viewing added 540 , 000 adults aged 18 - to - 49 ( a 38 percent increase over same - day numbers ) and 500 , 000 viewers aged 25 - to - 54 ( a 35 percent rise ) . eric goldman of ign gave " sometimes a great notion " an " incredible " rating of 9 . 5 out of 10 . the reviewer quoted the episode as " stronger and sadder than ever , " and was executed " extremely well . " goldman felt that the episode did not back down from the deeply powerful storylines from the past , and praised the emotions of the fleet after finding earth in ruins . the guardian received the episode positively , stating how many events happened during the course of the episode , and felt that the episode played fair with its audience , despite the number of new questions being addressed . it was anticipated that dualla would play a big part in the episode after her appearance from the cold open . her suicide was compared with boomer shooting adama in the closing scene of season 1 in a dramatical sense . the guardian also praised the performance between edward james olmos and mary mcdonnell 's characters , as well as the standoff between adama and tigh . matt norris of cinema blend stated that most of the events portrayed in the episode were unexpected , including dualla 's suicide , starbuck finding her own supposed body , discovering the thirteenth tribe were cylons , and that ellen tigh is the final model , but still thought the episode was among the top five battlestar galactica episodes in its run . marc bernardin of entertainment weekly stated that a lot had been going on in the episode , but criticised the writers ' decision of having ellen as the fifth cylon . while dualla 's suicide was surprising for bernardin , he was critical about the adama scene after her suicide , stating it as " some of olmos ' worst acting in the series " , and that the answered questions for the episode raised more questions , but felt the episode was good overall . alan sepinwall of the star - ledger commented : " what really grabs me about the show ( as i discussed in today 's column ) is its humanity , the way its characters react to situations the way you imagine real , contemporary people might " and felt that " as the stakes for the characters has risen , so has the intensity of [ the actors ' ] performances , " with even the extras in character . maureen ryan of the chicago tribune praised nankin 's directing , particularly " the moment in which we see kara thrace , silhouetted in black against a dark blue sky , preparing to burn “ her ” body — that ’ s sent a shiver down my spine . that was just such a beautifully operatic image , spot - on in tone and perfectly executed . 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