Daniel Radcliffe Pays Tribute to Late Harry Potter Co-Star Rob Knox!
Daniel Radcliffe has shared heartfelt words about his late Harry Potter co-star Rob Knox in a moving documentary that revisits the young actor’s life and untimely death. Rob, who portrayed Marcus Belby in Harry Potter and the Half-Blood Prince, tragically passed away before the film’s release.
A Brief Yet Memorable Role
Rob Knox’s role as Marcus Belby may have been brief, but it left a lasting impression on his castmates. He had signed on for the next Harry Potter installment, The Deathly Hallows, despite his character not appearing in the book a testament to his potential. Unfortunately, Rob’s promising future was cut short.
A Life Tragically Cut Short
In May 2008, just before filming was set to begin, Rob was tragically killed in a confrontation outside a bar in Sidcup, Southeast London. At only 18 years old, he stepped in to protect his younger brother during an altercation and was fatally stabbed. His death shocked the Harry Potter community and prompted an outpouring of grief.

Warner Bros. released a statement following the incident, expressing their sorrow and condolences to Rob’s family. The young actor never saw his performance on the big screen, as The Half-Blood Prince premiered a year later in 2009.
Daniel Radcliffe’s Heartfelt Tribute
Daniel Radcliffe, who starred as Harry Potter, reflected on Rob’s performance in the 2021 ITV documentary [K]nox: The Rob Knox Story. “I did one scene with him and you could tell just from that and the commitment that he entered into it with, that he was good,” Radcliffe said. He also penned a touching message shortly after Rob’s passing, writing: “Dear Rob, We are all proud to have known you and devastated to have lost you. It is terrible just to write this note. Rest in peace, Dan xxx.”

Remembering Rob Knox
The documentary sheds light on Rob’s life, career, and the events leading up to the incident. It also follows how his family has coped with their loss and explores the broader issue of knife crime in the UK.

Tom Felton (Draco Malfoy) also appears in the documentary, remembering Rob as “quite the joker,” reflecting the bright personality many of his co-stars admired.
A Call for Change
The man responsible for Rob’s death received a life sentence with a minimum of 20 years. The film not only honors Rob’s memory but also serves as a powerful reminder of the impact of violence and the importance of community action against it.