Zainab is the mother of Syed (Marc Elliott), Shabnam (Zahra Ahmadi), Tamwar (Himesh Patel) and Kamil Masood (Arian Chikhlia).

Born and raised in Pakistan, Zainab brought shame upon her family when she had an affair with Masood Ahmed (Nitin Ganatra), while married to Yusef Khan (Ace Bhatti).

Zainab arrives as the owner of Walford's Post Office,[2] clashing with employee Denise Wicks (Diane Parish) immediately, though they later become friends.

Zainab plans an extravagant wedding for Syed but she grows suspicious of the way Christian acts around him, and is incensed to discover they are having a homosexual relationship.

Amira leaves, and Christian's sister, Jane Beale (Laurie Brett), reveals to Masood that Zainab knew about the affair since before the wedding.

Tamwar starts seeing Afia Khan (Meryl Fernandes) and her father, Yusef, turns up and shocks Zainab as he is her ex-husband, whose family set her on fire.

Yusef, who moves to Walford as the new GP, attempts to reconcile with Zainab, suggesting that he was not involved when his family set her on fire in Pakistan.

Yusef manipulates Zainab, drugging her and causing her to pass out; she is hospitalised, with her family believing she took a deliberate overdose in a suicide bid.

Syed causes the family lose the restaurant because he has not paid the mortgage, and Masood finds out that Zainab took the money so asks her to leave because she promised never to lie after Yusef.

Zainab is angry to discover that Masood's brother AJ Ahmed (Phaldut Sharma) has informed the interviewer (Jonathan Sidgwick) that she has short-term memory loss.

Zainab buys an expensive water feature so that her neighbours will not think the family is poor, and she appears to care more about that than Masood.

In August 2015, Zainab is unable to return from Pakistan for Shabnam's planned wedding to Kush Kazemi (Davood Ghadami).

In 2024, Zainab falls ill and Shabnam plans to move to Pakistan with her daughter Jade Masood (Elizabeth Green) to care for her.

[3] Zainab Masood was one of several British Asian characters introduced in 2007 by the executive producer of EastEnders, Diederick Santer.

[5][6] The introduction of more ethnic minority characters was part of producer Diederick Santer's plan to "diversify", to make EastEnders "feel more 21st century".

[7] Prior to 2007, EastEnders was heavily criticised by the Commission for Racial Equality (CRE), for not representing the East End's real "ethnic make-up".

"[10] Actress and comedian, Nina Wadia—best known for starring in the sketch show Goodness Gracious Me—was approached and subsequently cast in the role of Zainab.

Wadia has commented: "I'm thrilled to join the show and I can't wait for Zainab to come to the Square and cause some trouble.

Described as "Walford's answer to Sir Alan Sugar", Zainab has a "direct manner" with "a tongue that could cut glass", which can be "hugely intimidating".

[2][4] This became evident shortly after the character's introduction, when Zainab become embroiled in an ongoing feud with her employee Denise Wicks (Diane Parish).

[17] Zainab and Masood are ready to settle down as Shabnam has left home, Tamwar is going to university and Syed is preparing for marriage.

An EastEnders source told entertainment website Digital Spy: "Zainab's in her mid-40s and was looking forward to spending some quality time with Masood, but the news certainly throws a spanner in the works.

Wadia said she cried on hearing about the storyline, saying that she was not looking forward to wearing a pregnancy suit: "From a purely aesthetic point of view, the thought of having to come in early to put on foam and then sweat while filming...

To be honest, if even one woman rings that Action Line at the end of the show and there's some difference made to her life, I'll feel like we've done our job," she continued.

The show's producer Lorraine Newman stated that "For the past five years Nina has brought to life the wonderful Zainab—the formidable, fun-loving, opinionated, fiercely competitive matriarch.

Nina's range as an actor is quite exceptional, from her comedic double acts right through to her ability to pull on our heart strings with incredibly moving drama.

"[21] Wadia has since said she would return if she was asked by producers, saying: "I miss EastEnders a lot, but after doing it for five and a half years it was time for me to go back to comedy and have a bit of a change.

Allsop said the scene was "totally unsuitable for 6.30pm" and added "I don't want kids watching that kind of rant – in time they'll know about bigots but please not yet.

"[26] The BBC responded by saying "Since this storyline began, EastEnders has always shown a balance of opinions to ensure that we capture the many different views of the characters involved.

[28][29] In 2020, Sara Wallis and Ian Hyland from The Daily Mirror placed Zainab 42nd on their ranked list of the Best EastEnders characters of all time, calling her a "Demanding matriarch" who had a "rocky" marriage to Masood.