Black Mirror Season 4: 10 Easter Eggs You Totally Missed
9. The Names Of The Planets
Sticking with the USS Callister episode, the planets Jesse Plemons and his Star Trek-lampooning crew boldly go to were seemingly named after a pair of murderers from Black Mirror season two's White Bear.
The planet Valdack flees to is called Rannoch B, while the world where Daly (Plemons) and Cole (Cristin Milioti) take a swim is named Skillane IV. In White Bear, Iain Rannoch and Victoria Skillane are a couple who brutally kill a young girl.
The planets' names are almost certainly a subtle call-back to the 2013 episode, although it's probably no coincidence that Rannoch also shares its name with a technologically hellish planet from the Mass Effect games.