The actress's character Zainab Masood has been manipulated by ex-husband Yusef for months, and the situation looks likely to intensify in the build-up to Christmas.
Ace Bhatti, who plays Yusef, has been part of the EastEnders cast since last year - and his alter ego's true colours have become increasingly apparent over the past few months.
Wadia told Inside Soap of the storyline: "I was filming out on location recently with Ace and a bunch of women came over to him and said, 'God, you're such a horrible man!' It's funny because Ace is such a sweet man - and you haven't even seen the worst of Yusef yet!"
Yusef receives a setback in next week's episodes when his scheme to make the Masoods think that baby Yasmin is not Syed's daughter is exposed.
However, Yusef soon returns to his old tricks by claiming that Zainab is to blame for the man he's become. He then continues trying to convince her to move to Pakistan with him.
Wadia continued: "Let's just say that what happens is the complete opposite of what you want to see. Zainab and Yusef share a dark and twisted love, and she definitely has feelings for him. It's not true and pure like what she used to have with Masood - and if Yusef manages to get her back to Pakistan, it will be the end for her.
"I wouldn't be surprised if Zainab ends up in some sort of home to recover from everything that's going to happen."
EastEnders continues on Thursday at 7.30pm on BBC One.
> EastEnders' Yusef shouldn't mess with Amira, warns Preeya Kalidas
> EastEnders' Christian is manipulated by Yusef - Spoiler Pictures
> EastEnders' Yusef faces a backlash - Spoiler Pictures
> EastEnders' December scripts are jaw-droppers, says Nina Wadia
> EastEnders' Masoods 'at centre of shock fire'
> Read Nina Wadia's recent interview with Digital Spy
> Read more EastEnders spoilers and news
Watch Zainab Masood's EastEnders character trail below:
Get the Inside Soap magazine on your iPhone or iPad