Neil McDermott is set to reprise his role as Ryan Malloy in EastEnders from September - despite his character being locked up in jail.
He has already started filming scenes at BBC's Elstree Studios where he is expected to have an emotional reunion with half-sister Whitney Dean, played by Shona McGarty.
Viewers watched on Tuesday as Whitney revealed to fiancee Lee Carter (Danny-Boy Hatchard) that she was pregnant, but she will soon discover he has cheated on her with best friend Abi Branning (Lorna Fitzgerald) when Whitney is diagnosed with chlamydia.
She'll need to lean heavily on her brother following the heartbreaking news.
A source told The Sun: "Ryan is never far from Whitney's mind and she has always stayed in touch as much as possible.
"Although Ryan will only be appearing in a couple of episodes it's fair to say that when he's around drama usually follows."
Ryan went on the run in 2011 after murdering pimp Rob Grayson, who was exploiting Whitney, during a brawl in the sea.
He made a surprise appearance this January, returning to look after his daughter Lily when his estranged ex Stacey Branning was sectioned.
But his time with Lily was cut short as he was taken away by police after admitting to manslaughter.