For me:
Ian bursts into Number 55 Victoria Road and catches Phil and Sharon off guard whilst they thrust each other excitedly during a passionate love clinch. Sharon screams and jumps of the sofa to grab her gown on the floor leaving Phil naked on the dining table. Ian runs over to Phil and grapples his throat.
Sharon: Ian let go of him! Are you crazy? He'll kill you! Ian! Ian!
Sharon runs out of the room.
Ian: (whispers into his ear) I know it was you Phil. I know what you did! You killed Lucy and I'm going to kill you. Why!?!?!
Phil is now unable to move physically so he now has to rely on his superhuman mental prowess. He stares into Ian's eyes and calibrates their minds.
Phil: I call upon the ancient gods of Kinross, Perth and Tulloch! INITIATE BODY SWAP!
Phil and Ian's minds are now exchanged.
Phil (in Ian's body): You came close, Beale. You've got my respect, but ... I WIN AGAIN!
Phil (in Ian's body) strangles Ian (in Phil's body) to death and exhales a breath of relief. Sharon runs in with Ronnie's gun to witness Phil's dead naked body sprawled across the dining table. She points the gun at Phil (in Ian's body), who she thinks is Ian.
Sharon: I don't know how or why you did it and I don't care. I don't care if I've known you for my whole life, that means nothing now you've done the ultimate evil and killed King Philith!
Phil (in Ian's body): King Philth?
Sharon: Yes, King Philith! That was my nickname for him and he'll never know it now thanks to you!
Phil (in Ian's body): Boy did I train you well! It's me Sharon, I swapped bodies with Ian just before my body died.
Sharon: What nonsense! That is the most ridiculous thing I've ever heard! I know some crazy things have happened in EastEnders, but do you really think anybody could actually switch bodies?
Phil (in Ian's body): EastEnders?
Sharon: Sorry, I meant Walford. Listen Ian, Phil or whoever you think you are as the new King Philith I've got a legacy to uphold.
Sharon cocks the gun and points it at Phil (in Ian's body)! This is it. After years of domination Phil the Unbeatable is finally about to go in the most disgraceful way possible. Killed by Sharon in Ian the weasel's body. But then he has an idea...
Phil (in Ian's body): So Sharon, you fancy being the new King Philith eh? I call upon the ancient gods of Kinross, Perth and Tulloch! INITIATE BODY SWAP!
Phil and Sharon's minds are now exchanged.
Phil (in Sharon's body): Goodbye Shazza, you were a good ride! (he pulls the trigger)
Sharon (in Ian's body): (crumbling to the floor) How dare you call me Shazza!
Phil (in Sharon's body): Yeah, well THAT was MINE AND SHIRLEY'S nickname for YOU! I win again ... AGAIN!
Sharon dies in Ian's body. Ian and Sharon are now dead at the hands of King Philith the Greatly Unbeatable. Phil (in Sharon's body) walks over to the mirror.
Phil (in Sharon's body): I could get used to these! (squeezes boobs). All this hair'll have to go though. (looks at Ian's body) Oh yeah, you only wanted to know why I killed Lucy! Guess I got a bit carried away

. Let's just say all will be revealed.
Phil (in Sharon's body) exits 55 Victoria road ready to wreak havoc in Walford in his new body.
Ben enters and sees his dad's naked body on the dining table and Ian Beale's body on the floor. He drops to his knees in tears.
Ben: YOU TWO SHOULD HAVE JUST TOLD ME! MY LIFE WOULD HAVE BEEN SO MUCH EASIER WITH A GAY DAD AND BROTHER/STEP-DAD
TBC...