The EastEnders spoilers from Monday's episode (September 5) will be released soon.
EastEnders has taken fans back in time to explain DCI Keeble's bitter feud against the Mitchell family.
For months, Alison Newman has been causing trouble for Phil (Steve McFadden), and recent episodes have suggested that she has an ulterior motive for pursuing him.
Keeble continued to pressure Phil to become a police informant in Monday's special episode. If he does not cooperate with Keeble, the iconic character would be sentenced to a long time in prison.
Phil was initially surprised to discover that Keeble wanted him to reveal information about his relative, Billy Mitchell (Perry Fenwick). The demand made no sense to Phil, since Billy only plays a minor role in the criminal world.
The story then rewinded to 1979, revealing how the Mitchell family were coping during a time of economic turmoil in the United Kingdom.
Peggy, played by Jaime Winstone, had her hands full managing a busy household. Eric's abusive relationship also causing her distress.
Eric deplores his new career choice when he learns that Phil wants to work in a local garage. He decided to take Phil and Grant on a criminal job to give them his "work experience."
Eric's dodgy plan involved stealing VCR recorders from a warehouse with the help of a corrupt guard.
Eric was given the risky task by Phil, Grant, and Billy, yet it went wrong when a second guard arrived, who wasn't part of the inside job.
Billy had climbed up to retrieve more VCR recorders from a high storage shelf.
Billy became panicked at the sight of the second guard and fell to the ground and injured himself, preventing him from making a quick getaway.
Phil ignored Eric's plea to withdraw from Billy, which resulted in the unplanned guard catching up with the criminal family.
After Eric said that he was a father to a young girl, Phil was unable to execute the brutal execution.
Eric took the revolver out of the chamber, unimpressed, and ordered Phil, Grant, and Billy out of the building.
As Phil waited, he heard a gunshot ring out from inside the warehouse, and knew that Eric had killed the helpless man.
The wife and daughter of a guard received the horrifying news from a policeman that he had been assassinated in a robbery later.
DCI Keeble was revealed as the little girl who was left without a father all those years ago in EastEnders' return to the present day.
Keeble knows that Billy was at the warehouse and she is blaming him for her dad's death; that is why she told Phil to provide her information.
"There were a lot of robberies in the late 1970s, and [Billy] was involved." Keeble said to Phil, "And when a security guard was murdered, he was also killed."
What will Phil decide to do?
EastEnders airs on BBC One Mondays, Tuesdays, Wednesdays, and Thursdays at 7.30pm. The program is also available on BBC iPlayer.
On our dedicated homepage, you can find more EastEnders spoilers.