Here's how Black Mirror’s "Rachel, Jack and Ashley Too" (season 5, episode 3) connects with the series’ shared universe. The storyline focuses mostly on the relationship between celebrities, fans, and music insiders, but there are also a few callbacks to previous episodes.
Black Mirror season 5's "Rachel, Jack and Ashley Too" stars Miley Cyrus as a pop singer (Ashley O) with her own artificial intelligence doll line (Ashley Too). She seeks authenticity and refuses medication in order to purse her artistic interests. However, Ashley O is drugged by her aunt/manager Catherine and forced into a coma. Meanwhile, 15-year-old Rachel (Angourie Rice) takes advice from her Ashley Too doll, much to the chagrin of her sister Jack (Madison Davenport), who likes alternative music more than pop culture trends. Ashley O’s dreams are exploited for content, allowing Catherine and her business associates to develop Ashley Eternal - a hologram version of Ashley O. By the final act, the doll is revealed to have a copy of the singer’s mind, and a technical glitch results in Ashley O awakening from a coma and pursuing a more edgy style of music.
There’s a roundabout quality to "Rachel, Jack and Ashley Too,” as the episode draws a connection between virtual reality testing in Black Mirror and fully developed concepts. “Playtest” (season 3, episode 2) features technology by SaitoGemu (and TCKR) that’s later used in “Striking Vipers” (season 5, episode 1). In "Rachel, Jack and Ashley Too,” SaitoGemu is referenced during a news broadcast about Ashley O’s coma. The ticker reads “SaitoGemu Shares Jump On Striking Vipers Release” - a clear reference to the Black Mirror season 5 premiere, "Striking Vipers."
In a more subtle form, "Rachel, Jack and Ashley Too” visually references the aforementioned “Playtest.” Rachel watches in amazement while conversing with an A.I. doll - a call back to when Wyatt Russell’s Cooper does exactly the same thing with a tiny hologram in "Playtest." The character staging and framing are nearly identical, only the final outcomes are much different. "Rachel, Jack and Ashley Too” essentially highlights what Cooper died for.
The most blatant reference connects "Rachel, Jack and Ashley Too” with the Emmy-winning episode “San Junipero” (season 3, episode 4). Upon being secretly drugged, Ashley O is taken to Saint Juniper’s Medical Center; a location that inspired the virtual reality realm known as San Junipero, which is revealed to be created by the aforementioned TCKR. Saint Juniper’s Medical Center is also home to a TCKR research division, evidenced by events from “Black Museum” (season 4, episode 6): Rolo Haynes, a museum owner, once worked in the TCKR marketing department, and Dr. Peter Dawson used TCKR’s “Symphatic Diagnoser” for medical purposes, only to become addicted to feeling the pain of others. Just as SaitoGemu is referenced in the news ticker during "Rachel, Jack and Ashley Too,” Rolo Haynes is referenced as well: “Museum Owner’s Body Found In Smoking Ruins."
For what it’s worth, the interactive Black Mirror release Bandersnatch reveals that a therapist named Dr. Haynes works at Saint Juniper’s Medical Center - another universe connection to "Rachel, Jack and Ashley Too." In addition, the Bandersnatch gaming company is called Tuckersoft, suggesting that TCKR - a shortened version of the name - would theoretically be developed years after Bandersnatch’s 1984 setting. Black Mirror may be an anthology, but it really is all connected.