Black Mirror: What is Sea of Tranquility?

Black Mirror has released its latest season Netflix and the hit series has as many Easter eggs as ever. Though connections between Black Mirror episodes have been previously established in other seasons, but the seem to be even more visible in season 6. One of the biggest recurring Easter eggs in Black Mirror is the fictional show-within-the-show, Sea of Tranquility. Viewers almost certainly noticed the multiple appearances by Sea of Tranquility in the season 6 episodes, but it's worth noting that this meta-joke isn't a new invention in Black Mirror but has actually been there since the beginning. So...what even IS Sea of Tranquility? 

The first mention of Sea of Tranquility comes in the first ever episode of Black Mirror, 2011's "The National Anthem."  In that episode, Prime Minister Michael Callow is blackmailed into performing an unsavory deed on a pig on live television as a means of saving a member of the royal family from being killed in a kidnapping plot. Before he is forced to carry that out by episode's end, attempts are made to cheat with one plan being an adult film star will act as Callow with a visual effects artist putting Callow's image on his head to sell the illusion. 

Enter, a minor character named Noel, a visual effects artist from an FX house called Blue Eye. According to another character in the episode "he won an Emmy for his effects work on that HBO moon western thing," which Noel then reminds him is none other than "Sea of Tranquility." That's about where it begins and ends, as no other references to Sea of Tranquility are found in the first two seasons of Black Mirror. Now, enter Netflix.

Black Mirror's Sea of Tranquiltiy connects most of the series together

Season three of Black Mirror, produced and released by Netflix, is quick to bring Sea of Tranquility back into the fold, one of countless Easter eggs seen in the show's American-produced episodes. In episode 3.01, "Nosedive," Bryce Dallas Howard's Lacie is in need of a ride and does her best to secure one from some Sea of Tranquility fans. The group is on their way to "Tranquility Con," dressed in costume with their fellow "Tranq Heads." 

We get a bigger idea of what the fake Black Mirror TV show is like here, as Lacie looks it up online to fake beign a fan. As seen on the page, Sea of Tranquility is described as "Japanese sci fi fantasy anime series" followiong: "Lt. Duster and his crew battle against the evil intergalactic empire putting their evil rules across the universe destroying and enslaving everything in their path. LT Duster is a former omega pilot who  defected from the cruel intergalactic empire." This marks the only time Sea of Tranquility is referred to as an animated project. 

The next reference to Sea of Tranquility is news that the series is being "rebooted," with references to new episodes of the show seen in Black Mirror season 5 episodes "Smithereens" and "Rachel, Jack and Ashley Too." With this week's new season of Black Mirror, even more references to Sea of Tranquility can be found. 

The Black Mirror episode "Joan Is Awful" has the most over reference, with Joan and her fiancé scrolling past Sea of Tranquility on the Streamberry app. A description for it can be found there too, reading: "HBO's seminal sci-fi western returns fo a climactic tenth series. Follow our intrepid crew as the manifest destiny far beyond safety of the Inner Worlds.." Sea of Tranquility then gets another reference in episode 4, "Mazey Day," when an actor named Justin Camley, said to star in the series, is found dead in his home.

So in short, Sea of Tranquility is whatever the writers of Black Mirror want it to be. It's a cheeky reference to TV and television fandoms that they can deploy without really committing to making fun of something specifically. It's also of note that yes, a book named Sea of Tranquility exists, from Emily St. John Mandel, but is not connected to Black Mirror at all.