Cosmo the Spacedog won't be brand new in the MCU for Guardians of the Galaxy Vol. 3, but the psychic canine will have a much more pronounced role in the sequel than in previous cameos, voiced by Borat 2's Maria Bakalova.
And with the Guardians of the Galaxy Holiday Special now streaming on Disney Plus, Cosmo has made her debut as a fully-fledged Guardians supporting character.
Yes, in comic books Cosmo is a male dog. But in the MCU, Cosmo is portrayed as female, partly in honor of Laika, the actual first dog in space (as confirmed on Twitter by director James Gunn).
With our real-world history lesson accounted for, what's the comic book history of Cosmo, the psychic dog who has often hung around with the Guardians of the Galaxy?
Get ready with your treats and tummy scritches as we explore the comic book backstory of Cosmo, Marvel Comics' cosmic canine.
Who is Cosmo the Spacedog?
Cosmo the Spacedog is a literal space dog!
Just like in the real world, the Marvel Universe experienced a decades-long Cold War between the United States and USSR, with the so-called 'space race' of the '60s marking the conflict's zenith. And just like in the real 'space race,' the USSR experimented with sending dogs into orbit (though Cosmo didn't appear in comics till 2007's Nova #8).
In the Marvel Universe, one of those dogs, aptly named Cosmo, wound up floating into space and being bombarded by Cosmic Rays - just like the ones that empowered the Fantastic Four, whose own comic book origins lie in the mythos of the space race.
The Cosmic Rays increased Cosmo's intellect and empowered him with psychic abilities. As a result, Cosmo became an interstellar traveler, eventually making his way to the cosmic locale known as Knowhere, a community inside the head of a dead Celestial.
Knowhere is, of course, the same location seen in the first Guardians of the Galaxy film, where Cosmo has a cameo as part of the Collector's Menagerie.
In comics, Cosmo eventually becomes the head of security for Knowhere, and it's in that capacity that he meets the cosmic superhero Nova (reportedly the subject of his own upcoming Marvel Studios film or streaming series) while he was on the run from a necromantic villain named Abyss, beginning Cosmo's association with Marvel's cosmic heroes.
Cosmo in the Marvel Universe
Cosmo then became embroiled in the conflict of Annihilation: Conquest, in which the evil AI Ultron conquered the techno-organic alien race known as the Phalanx and attempted to use their cybernetic plague to overtake the entire Marvel Universe.
As a result of Annihilation: Conquest, a new Guardians of the Galaxy came together consisting of Adam Warlock, Peter Quill, Gamora, Drax, Rocket, and Groot - in other words, the incarnation that was mostly adapted to the MCU.
Cosmo, while not technically an official member of the team, wound up becoming a close ally to the Guardians, who made their headquarters in Knowhere, where Cosmo was still operating as chief of security.
Then, during the story 'The Thanos Imperative,' the Guardians were forced to team up with Thanos to defeat an evil version of Mar-Vell, the original Captain Marvel, from an alternate reality. 'The Thanos Imperative' concluded with the disbanding of the Guardians and the apparent death of Peter Quill (who eventually got better) - but before his death, Quill tasked Cosmo with forming a new incarnation of the team.
Cosmo went on to found the Annihilators, a new cosmic team consisting of Silver Surfer, Gladiator of the Shi'ar, Quasar, Ronan the Accuser, and Thor's ally Beta Ray Bill.
The Annihilators were short-lived, and Cosmo found himself back at Knowhere, where he was poisoned by the villain Captain Skaarn, who attempted to conquer the station for himself.
Cosmo was saved by Nova, repaying Cosmo having saved Nova's life when they first met. And that was the last time Cosmo showed up in comics.
Cosmo in the MCU
Cosmo had a cameo appearance in Guardians of the Galaxy as part of the Collector's menagerie, but the now streaming Disney Plus Holiday Special and Guardians of the Galaxy Vol. 3 will put Cosmo in more of a spotlight (replete with telekinetic powers), and she'll have a full character presence in next year's Vol. 3, voiced by Maria Bakalova of Borat 2 fame.
Speaking of which, when Guardians Vol. 3 rolls around, there's a good chance she'll have some connection to the High Evolutionary. His comic book experiments often involve creating animal-human hybrids, or experimenting on evolving animals.
Director James Gunn has stated that Guardians Vol. 3 will be the end of this form of the team in the MCU - which means there's a chance Cosmo could wind up forming a new team like the Annihilators in the wake of the film.
The Guardians of the Galaxy Holiday Special is now streaming on Disney Plus. Guardians of the Galaxy Vol. 3 hits shelves May 5, 2023.
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