Black Widow star David Harbour may have just teased his potential appearance in Doctor Strange in the Multiverse of Madness.

Harbour recently posted a short ad for the laundry detergent Tide on his Twitter. The commercial starts out innocently enough, with the actor describing the type of stain on his shirt. At around the six-second mark, a dimensional gateway begins to open behind Harbour and directly beside the Tide container. A hand reaches out and grabs the container and pulls it into the gateway before it closes. Harbour then looks behind him to reach for the Tide and finds it gone. He looks back at the camera and utters, "Strange."

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Actors promoting an upcoming movie in a tie-in commercial is nothing new, but it is unusual for an actor to promote a film he has not been confirmed to be in. Harbour has only made one appearance in the Marvel Cinematic Universe to date, starring in 2021's Black Widow as the Red Guardian.

Harbour joins a long list of actors and characters rumored to have cameos in the Doctor Strange sequel. Since Patrick Stewart was confirmed to be reprising his role as Professor X from the 20th Century X-Men films, fans have been busy theorizing about who else from the MCU filmography might make an appearance in the sequel. Guesses have ranged from Tom Cruise as an Iron Man variant to the return of Inhuman Black Bolt.

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Doctor Strange in the Multiverse of Madness is set to unlock the MCU's Multiverse and push "its boundaries further than ever before," according to the film's official synopsis. The sequel to 2016's Doctor Strange finds the titular Master of the Mystic Arts as he "traverses the mind-bending and dangerous alternate realities of the Multiverse" with "the help of mystical allies both old and new ... to confront a mysterious new adversary."

The sequel will be the fourth project in the MCU to tackle the multiverse, following WandaVision, Loki and Spider-Man: No Way Home, all released in 2021. The film will also continue narratives established in WandaVision, with Elizabeth Olsen reprising her role as Wanda Maximoff / The Scarlet Witch.

Other cast members set to reprise their MCU roles include Chiwetel Ejiofor as Karl Mordo, Benedict Wong as Wong, Michael Stuhlbarg as Nicodemus West and Rachel McAdams as Christine Palmer. The film will mark the first appearance of Xochitl Gomez as America Chavez, a teenager with the ability to travel between dimensions by literally punching through them.

Doctor Strange in the Multiverse of Madness hits theaters on May 6.

Source: Twitter