EastEnders star Natalie Cassidy has teased the secrecy around plans for the soap’s 40th anniversary next year.

The BBC series is set to mark four decades on air next February, though details about what show bosses have in store have remained under wraps.

Natalie – who has played Sonia Fowler since 1993 – was asked about plans on yesterday’s (June 13) Lorraine, admitting that the show’s cast members are as in the dark as fans.

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“Yes February… we don’t know anything,” she said. “We keep saying, ‘What’s going on?'”

Host Lorraine Kelly then noted there’s usually a build-up of a storyline around Christmas, Natalie replying: “You’re hoping, a nice secret or something we need, don’t we?”

During the interview, Natalie also spoke about Sonia’s IVF storyline as she struggles to conceive a baby with Reiss Colwell.

“It’s been such a lovely storyline to play, the IVF, because it’s such a huge subject for so many people,” the actor said. “And I think what EastEnders always do best are the issues of life. And we’ve played it out – we’ve been doing it for eight to 10 months now.

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“You’re seeing the struggle,” she added, explaining that it is a challenge for “so many people”.

Natalie also revealed she’s received “lots and lots of messages on Instagram” from fans thanking her for “really playing it real”.

Lorraine then noted how the storyline shows the strain on couples, Natalie adding: “I think that’s what we’re showing, and now with the financial stuff that’s coming up, the decision that Sonia and Reiss have made.”