Watch: New trailer for Doctor Strange in the Multiverse of Madness

Marvel treated its devoted fanbase to a surprise over the weekend as viewers noted a shocking vocal cameo in the new trailer for Doctor Strange in the Multiverse of Madness.

Directed by The Evil Dead and Spider-Man filmmaker Sam Raimi, the movie will follow Benedict Cumberbatch's title character dealing with the devastating fallout of his multiversal meddling in Spider-Man: No Way Home.

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The film will see him cross paths with Scarlet Witch (Elizabeth Olsen) and, based on this new trailer, she's not happy — seemingly leading to her being pitted against Strange.

Eagle-eared fans, meanwhile, noticed that one scene from the jam-packed teaser appeared to include the sonorous tones of Patrick Stewart's X-Men leader Charles Xavier.

Stewart's voice can be heard as Strange is taken to a mysterious room, seemingly to face punishment for the ways in which he has destabilised time and space.

As he is led into the room, a character intones "we should tell him the truth" in what certainly sounds like the distinctive timbre of Professor X.

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This mysterious council of wise folk looks likely to be the Marvel Illuminati, which appears in the comics as a superhuman equivalent of the United Nations.

Notably, the group has featured a variety of characters over the years, including its founder Iron Man, Black Bolt of the Inhumans, Namor the Sub-Mariner and, excitingly, Reed Richards of the Fantastic Four.

Strange himself has also been a member of the Illuminati, even though he appears to be facing their wrath in this film.

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The idea of "variants" of MCU characters looks set to be a major part of the Doctor Strange sequel, with the sorcerer meeting a darker incarnation of himself in this trailer.

This would allow for the film to utilise the version of Professor X from the 20th Century Fox X-Men universe, while also leaving the door open for a new cast of mutants further down the line.

Marvel boss Kevin Feige has previously said that fans would have to wait "a very long time" for the X-Men to appear in the MCU, with Phase Four planned out prior to the 20th Century Fox merger.

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But certainly, with Spider-Man: No Way Home's parade of secret cameos, the MCU has shown a willingness to reach into past Marvel-adjacent properties to crowd-pleasing effect.

Doctor Strange in the Multiverse of Madness will be the next Marvel film out of the blocks, ahead of Thor: Love and Thunder and Black Panther: Wakanda Forever later this year.

It will feature return appearances from characters established in the first Doctor Strange movie from 2016, including Rachel McAdams' surgeon Christine Palmer and Benedict Wong as Wong — the current Sorcerer Supreme.

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There's also a return for Chiwetel Ejiofor as former Strange ally Baron Mordo, who broke bad at the end of the first film due to the sorcerer's time meddling — and can only have become more furious since.

Doctor Strange in the Multiverse of Madness is due to arrive in UK cinemas from 6 May.

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