Despite not knowing his father, Danny - played by soap newcomer Liam Bergin - arrives in Walford to attend Archie's funeral and curious to see his sisters. As Ronnie (Samantha Womack) and Roxy (Rita Simons) have a blazing argument, he interrupts them, but they're dismissive of his presence.
However, when Roxy states that they've just buried their dad, Danny retorts, "I think you might have buried mine, too." The Mitchell sisters are stunned by his response as they stare at the brother they never knew existed.
Described as a "loveable rogue", Danny's a charmer with an eye for the ladies, while guys instantly see him as competition in the alpha male stakes.
Danny's father Archie (Larry Lamb) met his maker during yesterday's episode when a mystery assailant fatally struck him over the head with the Queen Vic bust. He went to his grave knowing nothing of his son's existence, as his ex-wife Glenda (Glynis Barber) fled when she discovered that she was pregnant.
Speaking of his role, Bergin said: "The first time I walked into Albert Square and saw the Queen Vic was a very special moment and I'll have that memory forever. All of my on-screen family have made me feel very welcome from the first moment that I met them and I am enjoying every minute working here."
The BBC soap's executive producer Diederick Santer commented: "Liam is a fine young actor, and a proper East Londoner, who I've been keen to bring into EastEnders for quite some time. His character Danny Mitchell is something of an enigma."
He teased: "Is he simply their kid brother, keen to get to know his exciting big sisters? Or is there something else that he's after?”
Bergin's other screen credits include Five's 2009 Minder remake, Doctors and ITV's Trinity.
He began filming earlier this month and will make his first screen appearance at the end of January.