The identity of the man seen loitering around Albert Square and talking to Tiffany Butcher was revealed as Tony King's son, Leo King, in Monday night's episode of EastEnders.
He was first seen at Callum and Whitney's doomed wedding, and it was clear Bianca (Patsy Palmer) recognised Leo as she quickly ushered Tiffany (Maisie Smith) away.
Since then, Leo, played by newcomer Tom Wells, has turned up in Walford to rile Bianca by chatting to her daughter Tiffany again.
Although seemingly charming, Bianca knows Leo is desperate to clear his father's name as he is convinced he is innocent.
Leo also found out his grandparents gave Bianca money after everything that happened with Tony, and is on a mission to get back what he thinks is rightfully his...
Tom Wells, who previously starred in Doctors and Bancroft, said of joining EastEnders in this dramatic storyline: "I'm really excited to be joining the EastEnders team and seeing what’s in store for Leo.
"He’s definitely a man not to be trusted and I can’t wait to see him settle into Walford, it’s going to be fun."
Jon Sec, executive producer with the BBC One soap, added: "Bianca's return sparks a gripping new story with the arrival of Leo King – a dark and misguided figure who has grown up with the stigma of being the son of a convicted paedophile.
"We are thrilled to welcome Tom to the Square, knowing he will bring depth and complexity to the role of Leo, a man who believes his father has been wronged and who will also go to great lengths to prove it."
EastEnders airs on RTÉ One and BBC One on Mondays, Tuesdays, Thursdays and Fridays.