It’s an EastEnders mystery, wrapped up in an enigma and tied with a string of secrets…

No, not the Lucy Beale (Hetti Bywater) murder. This is the ‘Who’s Sharon’s real dad?’ riddle.

In the episode due to screen on Monday, August 17, Sharon (Letitia Dean) is with Abi (Lorna Fitzgerald), who is trying to write to her father Max (Jake Wood), who’s in prison on remand, charged with murdering Lucy.

“What do I even write?” Abi says to Sharon. “‘Hi Dad, please tell them that you killed Lucy’. It’s all so messed up…”

“You know, Abi… The last thing that I said to my dad was that I considered him dead,” Sharon told her. “I said I was an orphan.”

“Why? What did he do?” Abi asks.

“What didn’t he do?” Sharon replies, bitterly. “He lied, cheated… It was almost like it was in his DNA to hurt the people he loved the most.

“That’s what makes it so hard. You still love them, no matter what they’ve done.”

Now, of course, in this instance Sharon’s talking about Dirty Den Watts, who adopted her.

But we think this will lead to her talking about her birth father again. The one who has a big house in an expensive area of London. The one who everyone thinks is Gavin (Paul Nicholas), villainous husband of Kathy (Gillian Taylforth).

Gavin and Kathy are going to reappear very soon – and Sharon could be a bigger part of their story than many people realise.

EastEnders continues on BBC1, Monday, August 17, 8.00pm.