The episode kicks off against the festive backdrop of Bastille Day, where Donald 'Fitz' Fitzpatrick (played by Allan Hawco) and Genevieve 'Arch' Archambault (portrayed by Josephine Jobert) find themselves at the scene of what seems to be a car crash. Amidst the chaos, a John Doe slumps over the steering wheel, drawing their immediate attention.
As the investigation unfolds, Fitz notices a redhead in the gathered crowd, her eyes fixed intently on the proceedings. Alerted by Fitz's whispers to Arch, she swiftly bolts from the scene. In pursuit, they split up, with Fitz chasing her towards the rear fire escape of a nearby building, while Arch takes the alley route.
Fitz hotly pursues her, navigating the rooftop and jumping from one building to another until he finally corners her. Uncooperative and desperate, she makes a daring dash to the edge of the building and leaps into the void. In a heart-stopping moment, Fitz lunges after her but she narrowly misses the fatal plunge, landing instead on a small balcony of the building below. Left dangling precariously from the roof, Fitz is forced to watch as the redhead melts into the crowd below.
With Arch's help, Fitz manages to regain his footing on the rooftop and reveals that he had managed to grab the redhead's fanny pack during their struggle. Back at the station, Fitz, Arch, and Patty Montclair-Ito (played by Erika Prevost) delve into the fanny pack's contents, uncovering roofies and an itinerary that hint at the redhead's local ties rather than tourist status. Their conversation is momentarily interrupted by the arrival of Renuf Aucoin (played by Jean-Michel Le Gal), who announces that John Doe had offered 1,000 Euros to Tomas, a body shop worker, to use the car. Unperturbed by the car's poor condition, Tomas had eagerly agreed. This revelation also connects the dots to the victim's stay at the same hotel as Fitz.
Marguerite (played by Louise Pitre) enlightens them on the victim's identity, a man named John (surname unspecified), who had paid in Canadian money. She was also the one who had directed him to Tomas. A search of the victim's hotel room yields an astonishing discovery: five passports, a roll of duct tape, rope, and a silenced pistol. The passports bear the name John Steed.
Exiting the hotel, Fitz and Arch bump into Abigail Richards (played by Liisa Repo-Martell), a veterinarian staying at the hotel due to the police's road closure near her apartment. Fitz inquires if she had heard anything unusual the night of the incident, but she reveals she was occupied at a nearby farm delivering a breech calf at midnight.
Back at the precinct, Patty's efforts to match John Doe's fingerprints continued to yield no results. In the meantime, Arch tasked her with delving deeper into the redhead's background, while Fitz set about screening passports through Canadian Customs. Renuf gave Arch a hard time when she instructed him to retrieve yesterday's manifests, but his grievance soon dissolved under her sharp rebuke.
Inside the coroner's office, Emmanuelle (portrayed by Lara Arabian) revealed to Fitz and Arch an injection mark on John Doe's neck. Though toxicology reports were still pending, she had discovered an SD card among the deceased's stomach contents. Arch informed Fitz she would meet him back at the station, but he ignored her and tagged along anyway. She soon caught on, less than pleased by his persistence. Realizing she was on her way to see Sean Gallagher (played by James Purefoy), Fitz's curiosity led him to tag along despite her clear discomfort. As they walked, an unseen eye peered through the scope of a rifle, watching their every move.
Their interrogation of Gallagher proved fruitless. He claimed ignorance of anyone wanting him dead and had never laid eyes on John Doe. Their conversation stumbled further when Arch received an urgent call. Once Fitz and Arch left, Gallagher retreated to Marcus Villeneuve (Benz Antoine), expressing his displeasure at the unexpected visitors. He ordered Marcus to uncover the true nature of Arch and Fitz's inquiry.
Back at the station, Renuf reported that a customs agent had witnessed John Doe disembarking the first ferry to Fortune Island. Patty had identified the redhead as Zoe Derien (Annie Briggs), who had arrived from LaGuardia Airport the previous morning. Upon reviewing CCTV footage of Zoe's entry, Arch deduced that the hat she wore could only be purchased from a single store. Fitz also tasked Patty with examining the SD card retrieved from the victim's body, adding another layer of intrigue to the unfolding mystery.
While out shopping for a hat, Arch and Fitz encounter Marcus unexpectedly. They decide to escort him back to Arch’s place, not merely to bring him up to speed on their investigation but also to give him a thorough clean-up before resuming their duties at the station. During their visit, Fitz happens to cross paths with Kadeem Hamza (Sameer Jafar).
Back at the precinct, the team is informed that the SD card's contents are heavily encrypted, and John Doe succumbed to a pentobarbital overdose. Arch reveals that he knows someone skilled in decryption. As Veda Gonsalves (Ayesha Mansur Gonsalves) works tirelessly to unlock the SD card's secrets, Fitz reaches out to his former partner in Newfoundland for assistance in identifying the deceased. His partner comes through, identifying the victim as Louis Palmero (Chris Panting), the offspring of a prominent Montreal mob boss. An attachment accompanies the email, but the team must return to the station to open it to avoid disrupting the decryption process.
By the time Veda manages to decrypt the SD card, Fitz and Arch are already absent, and Patty lies unconscious in the bar area. When Veda rushes to her side, she too is rendered unconscious by chloroform. The perpetrator not only makes off with the SD card but also erases the security footage. Fortunately, Veda's encryption software automatically uploads to the Cloud, allowing her to access some of the card's data back at the station. What she uncovers resembles a lineup of plastic surgery patients. It dawns on Fitz that these are individuals who testified against Allesandro Palmero, depicting how they might appear post-plastic surgery. Soon after, Renuf informs the team that no pentobarbital was missing from the hospital, prompting Fitz to realize that veterinarians also possess this substance. Marcus reveals that Zoe's last known location was Morin Farm.
Upon arriving at the farm, Arch and Fitz discover the vet area in a state of disarray, with signs of forced entry evident everywhere. Intriguingly, a trail of handprints guides them to a bulky deep freeze, whose contents are shrouded in mystery. With barely a moment's hesitation, Arch pries it open, and out leaps Abigail, armed with a syringe filled with an unknown substance, lunging for Arch's neck. Using Abigail's own forward momentum, Arch expertly flips her over her shoulder, gaining the upper hand.
At the precinct, Abigail's true identity is unveiled: Lillian Bloye, a former plastic surgeon tied to the witness protection program. Though she once provided surgical services to vulnerable witnesses, some of her clients held considerable sway. Such was her fate that a mob enforcer eventually traced her steps. Before her handler could intervene, Lillian, panic-stricken, fled. She retained the incriminating photos on an SD card as her bargaining chip and confided in only one client, Baldwin (Zachary Bennett).
While Arch, Marcus, and Fitz confer in private, an abrupt blackout plunges the station into darkness. Moments later, they realize with a shock that Abigail has slipped through their fingers. Scenes later, Abigail is shown in the company of Zoe. Without much ado, Fitz and Arch track them down and, upon doing so, split up to surround them. Arch corners them first, and shortly thereafter, Fitz joins in, revealing Zoe as Abigail's handler in the midst of their confrontation. Suddenly, a sniper's bullet narrowly misses Zoe, prompting Arch to chase the shooter while Fitz secures Zoe's safety.
Before long, Arch and Abigail encounter Baldwin, who gains the advantage and prepares to execute Abigail. Just then, the Bastille Day fireworks explode overhead, creating a diversion that Arch exploits to disarm Baldwin. By this juncture, Fitz has arrived on the scene and takes Baldwin into custody from behind.
The team celebrates their triumph at Veda's, where Marcus offers everyone a toast with whiskey he procured from Gallagher. Both Fitz and Arch recognize it instantly. During the festivities, Veda playfully pins a Bastille Day emblem onto Marcus, unbeknownst to him that it contains a tracker. Later, Arch trails the tracker, ultimately stumbling upon a sleepwalking Fitz. The episode concludes with this intriguing twist.
