Kellie: 'I almost blew the Square up!'
The star, who reprises her role as Shirley Carter's daughter Carly Wicks this week, comes back to Albert Square on a pick-up truck.
But Kellie told The Sun: "The square is tiny so it's not easy to manoeuvre a great big truck around it, especially when you are as small as I am.
"I put on Carly's 5in heels and got in the truck, but as I started the engine and tried to drive in the heels I couldn't control it and ran over a load of electrical wires and almost blew the Square up."
She added: "We had to shoot the scene again, but they were so nervous about letting me back in the driving seat, they had to get a double to do it instead... I think everyone on set was quite relieved for their own safety after I got out."
Carly - who left four years ago to go travelling in Australia - returns to Walford with a baby after Phil Mitchell asks her to come and help her mum. Shirley has hit the bottle after the murder of her friend Heather Trott.
"I get a 'duff duff' music ending, so it was brilliant," said Kellie.
"I loved being back, even if it was only for a short while. The door is open so, who knows."