New pictures reveal the aftermath of the disaster, which will claim the life of at least one resident.
The locals are gathered in the Square for the Walford In Bloom celebrations, which are soon thrown into chaos when a fireball causes devastation.
Martin Fowler is seen panicking when he is unable to find pregnant wife Stacey in the moments following the incident.
There is also worry for the Mitchell family, as they soon realise Phil was near the the site of the explosion at the time - will he survive?
‘EastEnders’ bosses are currently keeping the identity of the victims close to their chest, but it has been confirmed at least one resident will not survive.
The aftermath of the explosion will also expose the dodgy dealings of Max Branning, played by Jake Wood.
Recently, he has been blackmailing his daughter’s boyfriend Steve Beale, who has been faking a brain tumour in order to trick Lauren into staying with him.
Actor Aaron Sidwell, who plays Steven, recently announced he was leaving the soap, making him one likely victim.
A source told The Sun earlier this week: “It’ll trigger a load of other storylines off the back of it, but the explosion itself will be a major talking point.
These episodes air week commencing 4 September on BBC One.
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