Harry Potter‘s Tom Felton Still Calls Jason Isaacs ‘Dad’ — and Yes, He Has Thoughts on that White Lotus Finale (Exclusive)

The actor spoke to PEOPLE about his long-lasting relationships with his former costars at the opening of the Harry Potter Shop Chicago

Jason Isaacs and Tom Felton in 2010’s ‘Harry Potter’. Photo: Warner Bros. Ent./Courtesy Everett Collection

Before he was scheming dad Timothy Ratliff on The White Lotus, he was scheming dad Lucius Malfoy in Harry Potter. And to Tom Felton, he’ll forever just be “dad.”

Speaking to PEOPLE ahead of the opening of Chicago’s new Harry Potter Shop, Felton said he’s still very close with his former castmates, particularly Isaacs, who played the wizarding guardian to his own young Draco Malfoy.

“I still call him ‘Dad’,” the 37-year-old admitted. “So we’re very close.”

Felton shared that the last time he saw the actor, 61, “he was just about to head off to Thailand to shoot The White Lotus.“

“I was thrilled to watch him do his thing,” he added.

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Tom Felton at the Harry Potter Shop Chicago. Courtesy Harry Potter Shop Chicago

Of the dramatic 90-minute finale, Felton said “it was great. I’m a big fan of the show, and the cinematography is so beautiful.” He continued, “Wickedly complex character storylines. I’ve had a lot of fun watching it. And Mike White is fantastic.”

Another series Felton has some interest in is the upcoming Harry Potter project, in the works at HBO.

“I think we’re all very excited to see the wizarding world continue,” he said, noting that he and his castmates haven’t spoken to each other about the series. “I look forward to knocking on young Draco’s door and surprising him, or something like that.”

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And if nothing else, “I’ll definitely be sneaking into a background shot as an extra,” he said with a smile.

The new Harry Potter Shop, situated on Chicago’s Michigan Avenue, features house and movie merchandise straight out of Potterheads’ dreams, in addition to a giant selection of candy as seen in the films and a speakeasy-inspired Butterbeer Bar with bakery. It is the fourth Harry Potter store in the world, following London, New York City and Tokyo.

Felton said that stepping into the space brought him back to his time on the Warner Bros. lot in England.

Tom Felton and Daniel Radcliffe in 2001’s ‘Harry Potter’. Everett

“Not only does seeing the house colors bring me back to being Team Slytherin all the way,” he said, “but the experience of the store is magical, for lack of a better pun.”

Felton even sent a video of the store to the Harry Potter cast WhatsApp group, as he shared that the stars are “all very tight still, very close. We’re usually in four corners of the earth at the same time, so it’s difficult to round us all up together. But Slytherins and Gryffindors are friendly.”

In addition to Felton, Isaacs and an impressively large cast, the eight-film franchise that spanned 2001 to 2011 starred Daniel Radcliffe as Harry Potter, Emma Watson as Hermione Granger and Rupert Grint as Ron Weasley.