‘Star Trek: Discovery’: Saru’s Shocking Secret, Revealed

Spoilers for Star Trek: Discovery “The Sound of Thunder” past this point.

We already knew that Saru (Doug Jones) wasn’t what we thought, but this week’s episode of Star Trek: Discovery completely redefined the character — and ultimately means big things for the series going forward. The episode, “The Sound of Thunder,” also gave us one of the creepiest Star Trek villains ever, and revealed some revelations about the season’s central mystery. But unless you were paying close attention, Saru’s secret may have gotten a little confusing. So allow me to Kelpiansplain it to you.

First of all, did you watch the Star Trek: Short Treks? No? If not, you missed the third episode of the digital series, “The Brightest Star,” which set up Saru’s origin story. Most of it was recapped this week, but essentially Saru grew up on the planet Kaminar with his sister Siranna (Hannah Spear) and father, a priest. When Kelpians start to go through a process called vahar’ai, they get sick and are ready for harvesting by the planet’s dominant species, the Ba’ul. Saru left before that happened, joined Starfleet, and later his father died and his sister became a priest.

Except, as we found out, the history of Kaminar isn’t exactly on the level. After encountering a signal from a massive sphere in “An Obol for Charon,” Saru went through vahar’ai and survived, with only his ganglia — protrusions from the back of his neck that emerged whenever he felt fear — falling off. It was gross. This week, we discover that under the ganglia is a new organ, one that can produce deadly darts, turning Kelpians from prey to predator.

And after some investigation from Michael Burnham (Sonequa Martin-Green) and Sylvia Tilly (Mary Wiseman), it turns out that the Kelpians used to be the dominant species on Kaminar until the technologically superior Ba’ul turned the tables, tricking the Kelpians into thinking they were defenseless. Thousands of years later due to some extremely helpful total non-interference from the Discovery that involves amplifying a signal all over the planet to activate vahar’ai in all Kelpians, and then blasting some of the Ba’ul’s murderous pylons, the tables are turned. Saru confronts one of the Ba’ul, a horrifying, dripping black monster with Ring-esque hair voiced by Mark Pellington, the director of Arlington Road and The Mothman Prophecies (really) and decides that the Kelpians won’t submit to the Ba’ul any longer, but neither will they become the predator species they were before. Instead, they’ll aim for balance.

For a character that has been defined by his fear, and challenging it… This is a massive status quo change. It seems at the end that Saru has made the decision to fight against his nature and be the good man he’s become with Starfleet, instead of the vicious monster the Ba’ul think he will become. That’s the mirror image of what we knew about him before, and it parallels what’s happening elsewhere in the episode. Hugh Culber (Wilson Cruz) is dealing with having an entirely new body with old memories after his surprise resurrection last week. And there’s the investigation of the Red Angel, which some folks on Discovery think is a threat, others a savior (it almost definitely seems the latter by the end of the hour).

And on a grand scale, that’s the ethos Discovery has been working with almost since episode one, showing people that have a split nature: Michael, a human raised on Vulcan; Ash Tyler (Shazad Latif), a Starfleet officer whose body is built on Klingon bones; everything in the Mirror Universe, including last season’s villain Lorca (Jason Isaacs); and now Saru. Ultimately, the show seems to be saying that we are more than our biology: we are our the product of both our upbringing, and the connections we make along the way. Nature is one thing; nurture another.

I’d also be remiss if I didn’t mention the title of the episode, a reference to the classic Ray Bradbury story “A Sound of Thunder.” You probably know the story best as the origin of the term “butterfly effect,” where a man travels back in time, steps on a butterfly, and changes the course of history. Here that’s a not-so-sneaky reference to the Red Angel, which everyone strongly suspects is a time traveler. But it’s also about how the initial conflict between the Ba’ul and the Kelpians spun out of control, and how Discovery’s little visit to the planet leads to near genocide. Small changes have big results, the episode posits… So what does Saru’s little change mean going forward? How will impact the crew’s journey, and maybe change the course of Star Trek as a whole?

Star Trek: Discovery airs Thursdays at 8:30/7:30c on CBS All Access.

Stream Star Trek: Discovery on CBS All Access