Whitney finds Leo hiding in the attic: EastEnders' Shona McGarty teases "intense and dramatic showdown"

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Viewers will know by then Leo is lurking in the loft and listening in on his ex-girlfriend's every move, and her discussing the letter with Kat Moon leads him to sneak down from his hiding place while everyone is out.

Determined to clear his dad's name, Leo seizes his opportunity to grab what he hopes will be the smoking gun to discredit Whitney's story she was groomed and sexually abused from the age of 12 by his late dad when he was the partner of Ms Dean's stepmum, Bianca Butcher.

"He thinks the letter will be the single shred of evidence that will prove everything," says Wells. "Leo is convinced it can prove his father's innocence and would stand up in court. Also, it's a tangible thing from his father, something that connects them."

Leo deliberately tracked down Whitney months ago and seduced her, before revealing his true identity and sinister agenda which drove him to wage a campaign of stalking and intimidation - but Wells insists his character still has genuine feelings for the person he's scaring half to death.

"Leo is very conflicted and is basically in love with the person he hates the most," explains the actor. "He blames Whitney for everything but in the same breath he loves her. Leo is a mix of emotions - he's furious, heartbroken and betrayed. He struggles to contain his emotions this week and as more information comes to light, he can't hide it any longer."

Meanwhile, worried Whit realises Leo is still lurking after her home is ransacked: "She's constantly looking behind her, it's just horrible," sighs McGarty. "Everybody's stressed to her how much danger she is in and she trusts her family and friends. She is worried about what he's capable of."

Echoing Wells' summary of their complicated relationship, McGarty agrees her alter ego still feels affection towards Leo, in spite of what he's done. "Whitney really does see the good in everyone and still wants Leo to be happy, which proves how nice she is. Even though he is Tony’s son and it’s awful and tragic as they can never be together, she does kind of still hold a flame for him."

The stage is set for Leo to make his presence known to his prey, and as the soap hurtles towards it's 35th anniversary week the storyline is set to be a key part of the big plots. Whitney is on her way to the doomed Queen Vic boat party, but stops in her tracks when she sees Leo waiting in her bedroom…

"She's been oblivious that Leo is in her loft which is just terrifying. The week ends with a very intense dramatic showdown…"

Driven to the point of obsession to get revenge for Tony, Leo's emotions boil over and the situation takes a dangerous turns. According to show insiders, someone will be left with blood on their hands - but who?

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