Warning: Spoilers for Behind Her Eyes ahead! Behind Her Eyes, the new Netflix adaptation of Sarah Pinborough's 2017 novel, seems like your run-of-the-mill psychological thriller miniseries—until it suddenly does not. Where many similar shows would be content to devote their entireties to dissecting the bevy of childhood trauma, addiction struggles, and marital issues set up within this series' first few episodes, Behind Her Eyes decides instead to stray just a teensy bit from that well-worn path by throwing dashes of witchcraft, arson, and murder, plus a healthy dose of supernatural body-switching into the mix.
That last bit is particularly confounding: Throughout the series, several characters are shown learning to master the concepts of lucid dreaming and astral projection in the span of, like, five minutes (?) under the guidance of Adele, played by Eve Hewson, who is casually self-taught (??) in the ancient art of sending her soul on quick day trips to places she's been before and into other people's bodies for longer residencies (???). But while all of that may be extremely difficult to believe, astral projection and lucid dreaming are actual phenomena—even if scientists aren't completely sold on all the details. Here's what you need to know about the concepts; thanks in advance for not using them to murderously body-switch your way closer to the man of your dreams.
What is lucid dreaming?
As seen in Behind Her Eyes, the first step to being able to launch your soul onto the astral plane at will is mastering the practice of lucid dreaming, a longstanding concept that gained a much broader audience a decade ago, thanks to Inception. Lucid dreaming allows a sleeping person not only to become conscious of the fact that they're in a dream, but also, often, to take control of the dream and change its storyline as they see fit. It's a well-documented practice that has been around for centuries, confirmed through scientific study, and used for the treatment of PTSD and nervous system damage.
In the series, Adele, Rob, and Louise all try out lucid dreaming to overcome their night terrors. Rather than simply being satisfied with a good night's sleep, however, all three quickly learn how to take things a giant step further by conquering astral projection, too.
So, what is astral projection?
The idea of astral projection is far less medically sound than lucid dreaming. There certainly have been documented cases of out-of-body experiences, in which a near-death situation, neurological trauma, or hallucinatory drug use can send a person into an involuntary dissociative state, per Healthline, but the act of consciously sending your soul out of your body to "travel" elsewhere, as Adele puts it in Behind Her Eyes (let alone to take over someone else's physical form) is regarded as more of a spiritual practice than a scientific one.
The biggest cultural touchpoint here is probably Doctor Strange, in which the titular medical professional does indeed have to wrestle with the conflict between science and spirituality as he learns to magic himself around the world and into various dimensions. As seen in Doctor Strange—though not in Behind Her Eyes, which posits that astral projection begins with a lucid dream—a main difference between lucid dreaming and astral projection is that the latter is typically believed to be done while the projector in question is still awake.
Can you learn to lucid dream and astral project?
Lucid dreaming is actually fairly simple to attempt. There are a variety of methods just a Google search away, but one of the most common revolves around building habits throughout your waking life that will carry over to your dreams to serve as "reality checks." You might remember that the characters in Inception carry various "totems" around that act differently depending on whether they're in the real or dream world, while the characters in Behind Her Eyes rely on habits like pinching themselves, constantly telling themselves they're awake, checking clocks, and counting fingers.
Astral projection, meanwhile, is not nearly as simple, nor are its methods as widespread. Fortunately for anyone looking to send their soul on a quick vacay, there are several books and podcasts out there for astral projection beginners. Or, once you've become a lucid dreaming expert, you could always try out the Behind Her Eyes route and, while dreaming, visualize a series of doors leading to places you've been before. Happy projecting!