On Friday, viewers will see Steven – played by 18-year-old Aaron Sidwell – reveal his father Ian's (Adam Woodyatt) whereabouts to his petrified sister Lucy (Melissa Suffield).
For weeks, Ian has been locked in the same block of flats in which he discovered that his son had been stalking him. Pretending to be his dead mother Cindy, Steven had been sending gifts and messages from beyond the grave.
As Steven leads his sister through the eerie corridors of the flat, Ian startles them when he jumps out of nowhere.
While a struggle between father and son ensues, Lucy sneaks away and calls her stepmother Jane, who rushes to their location where a final showdown takes place.
With Steven holding his father at gunpoint, Jane rushes into the flat. As she and Steven tussle for the weapon, a shot rings out and it's Jane who takes the bullet.
An EastEnders source told DS: "Jane's worried sick when she can't find Ian, Lucy or Steven. When she turns up at the block of flats, she can't believe what she's faced with."
They added: "When the gun fires, Jane's life is left hanging in the balance…"
The shooting scenes are to air on Friday, October 12 with the aftermath transmitting on Monday, October 15.
