Game of Thrones is an American fantasy drama television series created by David Benioff and D. B. Weiss.
 It is an adaptation of "A Song of Ice and Fire", George R. R. Martin's series of fantasy novels, the first of which is "A Game of Thrones".
 It is filmed in Belfast and elsewhere in the United Kingdom, Canada, Croatia, Iceland, Malta, Morocco, Spain, and the United States.
 The series premiered on HBO in the United States on April 17, 2011, and its seventh season ended on August 27, 2017.
 The series will conclude with its eighth season in 2018 or 2019.
"The Snow Queen" is the seventh episode of the fourth season of the American fantasy drama series "Once Upon a Time", which aired on November 9, 2014.
"Dark Hollow" is the seventh episode of the third season of the American fantasy drama series "Once Upon a Time", and the show's 51st episode overall.
"Five-Twenty-Ten" is the seventh episode of the fifth season of the American Fox science-fiction/drama television series "Fringe", and the show's 94th episode overall.
 The episode premiered in the United States on November 16, 2012.
Once Upon a Time is an American fantasy drama television series that premiered on October 23, 2011, on ABC.
 The show takes place in the fictional seaside town of Storybrooke, Maine, whose residents are characters from various fairy tales transported to the "real world" town and robbed of their original memories by a powerful curse.
"Requiem" is the seventh episode in the fifth season, and the 101st overall episode, of the American crime drama television series "NCIS".
 It first aired on CBS in the United States on November 6, 2007.
 The episode was written by Shane Brennan and directed by Tony Wharmby.
"Crossed" is the seventh episode of the fifth season and 58th episode overall of the post-apocalyptic horror television series "The Walking Dead", which aired on AMC on November 23, 2014.
 It was written by Seth Hoffman and directed by Billy Gierhart.
 In the episode, Michonne and Carl Grimes stay at the barricaded Church with Gabriel Stokes as Rick Grimes and the others go on a rescue mission for Beth Greene and Carol Peletier in Atlanta.
 The episode received generally positive reviews, though most noted the set up for the mid-season finale.
 This is the first episode to feature all credited series regulars for the fifth season.
"Heartless" is the seventh episode of the sixth season of the American fantasy drama series "Once Upon a Time", which aired on November 6, 2016.
"Nimue" is the seventh episode of the fifth season of the American fantasy drama series "Once Upon a Time", which aired on November 8, 2015.
The sixth season of the fantasy drama television series "Game of Thrones" premiered on HBO on April 24, 2016, and concluded on June 26, 2016.
 It consists of ten episodes, each of approximately 50–60 minutes, largely of original content not found in George R. R. Martin's "A Song of Ice and Fire" series.
 Some story elements were derived from the novels and from information Martin revealed to the show-runners.
 The series was adapted for television by David Benioff and D. B. Weiss.
 HBO ordered the season on April 8, 2014, together with the fifth season, which began filming in July 2015 primarily in Northern Ireland, Spain, Croatia, Iceland and Canada.
 Each episode cost over $10 million.

Question: Which  American fantasy drama television series is  "Nimue"  the seventh episode of the fifth season
Answer: Once Upon a Time