Lacey, 25, says that Stacey will have to face people who aren’t as happy as cousin Kat Moon about her return.
Speaking to a UK newspaper, Lacey said: “The next couple of weeks are going to be pretty dramatic for Stacey as she has to face up to her past and work out if she can stay in Walford.
“She also has the added drama of having to face those who may not be pleased to see her. The next few weeks are certainly not going to be dull.”
When she was last on the show, Lacey was involved in some huge storylines, including Stacey being diagnosed with bi-polar disorder and beginning an affair with her husband's dad.
Viewers took to Twitter to announce their excitement for Stacey’s return last week, and Lacey admitted she is just as excited.
She said: “I love the show and it’s a massive part of my life. I feel like I grew up here as I was 16 when I first started. It was lovely to have a break and try other things, which was why I left in the first place.
“But it’s also very nice to come back. It’s like when you’ve been on a long journey. You get home and you think: ‘Thank God I’m home.”
The actress revealed she was nervous about rejoining the soap, and felt she might have forgotten how to play one of the show’s best loved characters.
She said: “Before I started filming, I was pacing around my flat thinking, ‘Ah, what if I’ve forgotten what Stacey’s like?’
“Then I got to work. I was shaking doing my first scene! But after that it felt like I hadn’t been anywhere. Stacey just sort of came out again!”