Charlie Brooks is to reprise the role of evil Janine, last seen returning for Frank's funeral in April.
She said of her return: "I'm thrilled to be returning to
EastEnders
. I loved coming back earlier in this year for Frank's funeral. It gave me a taste for playing Janine again. And I'm excited to see what Janine will be getting up to now she is returning to Albert Square."
EastEnders
executive producer Diederick Santer said of the signing: "I couldn't be more pleased that Charlie Brooks is rejoining
EastEnders
. With her appearances last month, she reminded us what a fine actress she is, and what an intriguing, watchable and engaging character she plays as Janine.
"Rejoining us for a longer stint will give us a chance to understand what makes Janine tick, to see what lies beneath the surface of this unique character, and to find out where she got that flashy big black car."