The (not-so-kept) secret is out: Tilda Swinton has confirmed she is the actress playing 82-year-old male psychiatrist Dr. Jozef Klemperer in Luca Guadagnino’s “Suspiria.” For months now, Amazon Studios and “Suspiria” cast and crew have been claiming the character is played by Lutz Ebersdorf, with Swinton even reading a statement on behalf of Ebersdorf at the film’s Venice Film Festival press conference. The actress finally came forward in an interview with The New York Times about Klemperer’s real identity

“Undeniably, I would have to say, for the sheer sake of fun above all,” Swinton replied when asked why she wanted to take on the role. “As my grandmother would have it — a motto to live and die by — ‘Dull Not To.’”

Swinton was transformed into an 82-year-old man with the help of Oscar-winning makeup artist Mark Coulier. The two worked together on Wes Anderson’s “The Grand Budapest Hotel,...