Episode 1 is the first episode in the B: The Beginning series. It premiered on March 2, 2018.
Summary[]
Keith rejoins the RIS just in time to work a brutal double murder involving "Killer B." Then an unknown group steals a military vehicle for a rampage.[1]
Plot[]

A woman runs from her kidnappers—unable to speak or take the duct tape off her mouth.
A woman is running in fear through a dark forest at night. She is unable to scream as duct tape covers her mouth — nor can she take the tape off her mouth as her arms are strapped behind her back. Two brothers -- Henry and Richard Crouse -- with recurve bows and night vision goggles gleefully chase her across the forest. Their other brother-- Julian Crouse -- is in a van watching through a live feed from the night vision goggles and laughs manically. The woman is shot down with an arrow through the leg and falls to the ground in agony. A mysterious red-haired man observes this from the carpark where the van in parked.
The Crouse brothers question whether the woman is dead, and pull the arrow out of her leg to find out. She writhes as the arrow is pulled out to the further delight of the brothers. They prepare to dissect her with a pair of plain metal shears.
Out of nowhere, a storm of feathers and a blue blade descends on the two brothers in the forest and decapitates both before they are even aware of it. Julian Crouse cries this brothers' names in grief and denial at the sight of his dead brother's decapitated head on the night vision feed when a single large, inhuman eye enters into view of the night vision lenses and is shown through his tablet. Julian screams in horror.

The episode then cuts to a young man, and then further to an aerial view of a charming seaside town called the "Old Town". The young man -- Koku -- is walking leisurely on top of the very peaks of roof tops and casually jumps off the three storey building to street level. He walks from the inner town to a two-storey house located in the outer suburbs after buying a number of red bean buns that had been baked that morning by a baker in the town. It is also the workshop of a family of luthiers and thus bears a sign with the family's business' name: "Stella del Mattino".
A young woman in a uniform jacket proclaiming her to be part of the RIS -- Lily Hoshina -- races out of the house, shouts that she's late to Koku, and drives away in a hurry. She quickly drives back soon afterwards, shouting that she has left her ID behind. It is implied that Lily accepts the red bean buns that Koku offers to her as she later offers it to her colleague Boris.
The episode cuts to Lily's car driving up a mountain road through the forest of the opening scene, to arrive at the scene of the Crouse brothers' murder. After surveying the infamous Killer B mark, Lily goes to show a civilian off the premise. After Boris recognizes the civilian to be Keith Flick, Keith greets Lily with a noncommittal "yo".

When they return back to RIS located at the Coastal Branch, Jean debriefs Keith while Brandon gapes at seeing the legendary Keith Flick in the flesh. Mario quietly observes and closes the drawer full of books on Keith Flick, suggesting that he was a prominent figure in the police world but is now a "has-been" who left hands-on detective work 10 years ago.
Eric introduces Keith saying that he rejoined the Royal Investigation Service unit from the Archives Division. This is followed by Keith, after being prompted by Jean, to gesture quotation marks in the air. This is meant to signal "Like Eric Said" and Keith does not offer any other introductory comments which is fitting for a recluse like himself.
Eric starts off the morning meeting by disclosing the names of the deceased, Henry and Richard Crouse, and confirming that both were killed by a sharp blade. The other victim, the woman, was still alive and receiving medical treatment at the hospital. It is mentioned that she was abducted and raped by the Crouse Brothers and that the third brother Julian was still missing. Eric advises that Killer B's signature was found at the scene of the crime and that so far, Killer B has been involved in 15 killings in the past few years. All of this occurs while Lily is in the background pensively analyzing something on her tablet which the aloof Keith notices.

Viewers can see that Julian, who was in the blue van, has pulled up unsuspectingly to a stranger's house as the van is parked messily. The door is wide open revealing dead bodies in the foyer and the kitchen. The red-haired man steps inside and finds Julian watching the television with news of his dead brothers and behaving erratically, firing off a shot in the otherwise quiet house and muttering that he would kill whoever did that to his brothers. The red-haired man offers to help him in return for a favour.
Keith goes to visit his childhood friend Gilbert who works in the Forensics Lab specifically the Coastal Branch. Gilbert smiles when Keith comes in and calls him Genie. As they drink bitter coffee, Gilbert tells Keith he quit smoking and they reminisce about a shared tragic past. Keith wordlessly takes notice of the white orchids surrounding Gilbert's office and leaves, only to return and toss Gilbert a cigarette pack. Gilbert looks at it, sniffs himself and wonders how Keith knew he was lying.
Kaela calls for army and municipal assistance as a red I.F.V. (infantry fighting vehicle) wreaks havoc in the city by shooting down army convoys. It is announced that the Royal Family declared martial law in response to the emergency. The team's radio messages are listened into by Killer B and viewers see that at least 10 faces are marked with Xs, all but the red-haired man and an unnamed man.

Mario, Brandon, Lily and Boris are seen to be chasing after the red tank while Julian is screaming to taunt Killer B into revealing himself. The red-haired man is driving the tank while Julian shoots other vehicles trailing them. The red tank releases gas and escapes into a tunnel.
There is a group shown to be disposing the red tank while Julian suspiciously follows the red-haired man. They change vehicles and get onto a boat, viewers see police officers patrolling the area on land and in air. Eric figures out that the hybrid I.F.V. has not been unveiled to the public and Keith informs that rumours are that a corrupt military country has been developing it in secret and this vehicle type is known as Five-O. As this point, Keith gets interested in the case and deduces that the perpetrators used the closed Alpha Metro line and are at the Museum of Flight.
The red-haired man has stolen a National Freight train 645 and is threatened by Julian at gun-point. Killer B arrives on top the train to which Julian is ecstatic about, but is abruptly sliced by the red-haired man. As he secretively dials a number to what we presume is to notify someone, Killer B says that he is someone that deserves to die. As Quinn lunges to attack, Killer B rises and reveals his left arm as it turns into Lohengrin, a dark blue blade. As Killer B strikes Quinn's forehead, it turns dark grey and spreads. Quinn eagerly charges ahead only to have his head sliced in half by the blue blade and disintegrating with a scream. The long-haired man sits in a blimp, looking down at Cremona with a smile.

The RIS arrives at the train wreck site and Keith examines blue powder between his fingers, realizing he got it wrong and that the wreck was the main objective. As Lily complains that Eric is closing the case, Brandon excitedly shares the wreckage viewed from above spells Killer B.
Killer B says he will not stop killing until he is found, the long-haired man says he has found Killer B and Keith saying that he will find him. The episode closes with Killer B saying he will be right here waiting.