After an unbelievable mid-season cliffhanger and a six-week hiatus that made room for the equally impressive Star Trek: Prodigy, Star Trek: Discovery returns for the second half of its fourth season in thrilling fashion. Following Cleveland “Book” Booker and Ruon Tarka’s theft of the Federation’s prototype spore drive, the pair departed on an unsanctioned mission to destroy the Dark Matter Anomaly (DMA). As we return, Admiral Vance deploys Starfleet in an effort to locate the two fugitives…
Angered by Captain Burnham’s inability to predict Book’s actions, Federation President Rillak sidelines U.S.S. Discovery-A from the pursuit, assigning Burnham to conduct research on Species 10-C, the creators of the DMA, in preparation for first contact. Aware that Tarka will require a supply of isolynium to assemble the isolytic weapon necessary to sever the DMA from its power source, Federation Intelligence identifies four potential vendors who sell the black market element and dispatches vessels to those locations.
Having personally recruited Tarka for his scientific expertise, Vance feels guilt over the Risan’s apparent betrayal and secretly meets with Burnham. The admiral must display solidarity with Rillak in public, but he orders the captain to employ her cunning mind to find a way to stop Book within the scope of her mission to learn more about Species 10-C.
As part of that assignment, Burnham meets with Saru and Stamets, who report that the lack of data about the region beyond the Galactic Barrier is impeding their efforts. Zora informs the group that the Sphere, last seen in season two, holds information about a warp-capable civilization living near the Barrier who would surely have star charts for the region. Unfortunately, the Orions are the only local group to have dealt with that species.
This development provides Burnham with the opportunity she needs to pursue Book. The captain suggests she meet with Haz, a broker who can get her the stellar surveys… and also the person she suspects Booker will reach out to about the isolynium. The assumption proves correct, as Book brings Tarka to Haz’s casino-slash-underground fighting ring, an establishment that makes Quark’s Bar on DS9 seem like a reputable hangout.
Haz attempts to sell the duo scanners made by the Devore, the Delta Quadrant power encountered by Captain Janeway in “Counterpoint.” Known to the broker by the nickname “Glowworm” (likely a reference to his days saving trance worms), Book discovers that Haz believes the former courier still owes him a debt from years past, so he will need additional latinum to secure the rare element. “Glowworm” successfully proposes that he and Tarka track down card counters in the casino as payment.
En route to Haz’s in a shuttle, Burnham has brought Lt. Commander Owosekun as her backup. Citing Owosekun’s brief disagreement with Saru in “Stormy Weather,” the captain tells her appreciative subordinate that she wanted her to be able to contribute to the mission. Haz agrees to sell Burnham (a.k.a. “Right Hook”) the star charts, but says she will need to win more funds in the casino to outbid Book for the isolynium.
Back on Discovery, Dr. Culber suffers through his own guilt trip over not identifying the true extent of Booker’s distress. Stamets intervenes, allowing the two to have a beautiful discussion regarding the nature of anxiety. It’s yet another wonderful moment where Discovery tackles the stigma of mental health head-on. Plus, we learn that the DOTs clean the crew’s quarters for them!
Unable to detain Booker due to the Federation’s lack of jurisdiction on the planet, Burnham approaches her partner diplomatically, but fails to persuade him to stand down. In order to attain more latinum and outbid Book, Burnham permits Owosekun to enter into a hand-to-hand combat competition. Michael hypes up the gamblers to bet on Joann “Oh Wow!” Owosekun, but the ops officer loses the first two fights.
However, the defeats are a ruse to influence the betting odds in their favor. Burnham wins enough money for the isolynium when Owosekun trounces her opponent in the third round. Meanwhile, Tarka identifies a potential card counter, only to realize that the cheater is actually a Changeling (DS9 and Dominion fans rejoice!) who shapeshifts to avoid detection. With the Founder apprehended, Book and Tarka also have enough to pay for the isolynium. The solution? A high-stakes card game, of course!
Unfortunately, two Emerald Chain holdouts enter the game, as well. Knowing it would be unacceptable to allow the Chain’s remnants to attain isolynium, Burnham and Booker covertly collaborate to outmaneuver Osyraa’s former minions. Once they become the only remaining participants, the captain and Book go all in on their bets… with “Glowworm” unveiling a winning hand that earns him the coveted isolynium.
At Federation Headquarters, Burnham surprises Vance and Rillak when she discloses that she had discreetly placed a tracker on the isolynium container, so they now have Book’s exact whereabouts. Stamets studies the new star charts and learns that Species 10-C’s technological capabilities are beyond comprehension, as they have constructed an artificial structure (a ‘hyperfield’) large enough to conceal an entire star system. Burnham theorizes that the DMA is actually a mining implement designed to harvest energy-abundant boronite, the same substance the Borg used to synthesize the powerful Omega particles in Star Trek: Voyager.
“All In” balances astonishing revelations related to Species 10-C with superb character moments, particularly those involving the tension that continues to build between Burnham and Book. Owosekun and Tarka share an intriguing scene that allows the ops officer to hypothesize that the Risan scientist’s actions are motivated by a deep loss. Armed with a better understanding of Species 10-C’s destructive potential, the Federation realizes it must capture Booker and Tarka immediately or risk a war with the advanced civilization. The second half of Discovery’s fourth season is already shaping up to be an exhilarating adventure. Stay tuned as we continue to boldly go…
Jay Stobie (he/him) is a freelance writer and consultant who has contributed articles to StarTrek.com, Star Trek Explorer, and Star Trek Magazine, as well as to Star Wars Insider and StarWars.com. Jay serves as a BoldlyGo Campaign Ambassador for The Roddenberry Foundation. Jay can be found on Twitter and Instagram at @StobiesGalaxy.
Star Trek: Discovery currently streams exclusively on Paramount+ in the U.S. Internationally, the series is available on Paramount+ in Australia, Latin America and the Nordics, and on Pluto TV in Austria, France, Germany, Italy, Spain, Switzerland and the United Kingdom on the Pluto TV Sci-Fi channel. In Canada, it airs on Bell Media’s CTV Sci-Fi Channel and streams on Crave. Star Trek: Discovery is distributed by ViacomCBS Global Distribution Group.