Lucky the Pizza Dog is Kate Bishop's adopted golden retriever in Hawkeye, but the Marvel Cinematic Universe character may have a secret identity. Lucky (played by Jolt) makes his debut in Hawkeye when he helps Kate Bishop (Hailee Steinfeld) fight off the Tracksuit Mafia. The dog shows up out of the blue in the series to try to stop a Tracksuit Mafia member from stealing Avengers property, and Bishop later saves Lucky from traffic. Though he's mainly on the periphery of Kate and Hawkeye's adventures in the series, staying out of most of the main action and fight scenes, he's still a part of their team. Lucky even goes along for the ride to Clint Barton's home, spending the holidays with Hawkeye's family.

Besides Lucky and Kate Bishop, Hawkeye introduces several other important MCU characters. In the series, Maya Lopez (Alaqua Cox) makes her debut. Lopez is Deaf and a member of the Cheyenne Nation in Marvel's comics. Likewise, Cox is a Deaf actor in real life and is also Native American. Additionally, Hawkeye episode 5 revealed Vincent D'Onofrio's Wilson Fisk/Kingpin was part of the series. Hawkeye finally connects Netflix's Marvel shows to the MCU by including the character, who first debuted in Daredevil.

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Though Lucky is already a significant part of Hawkeye, the dog may have a deeper purpose in the MCU. According to a fan theory (via Reddit), Lucky is secretly Cosmo the Spacedog. Cosmo previously appeared in the Guardians of the Galaxy films, where he was initially part of The Collector's (Benicio Del Toro) collection and played by a dog named Fred. However, Howard the Duck (Seth Green), who was also part of the collection, winds up at the battle against Thanos (Josh Brolin) in Avengers: Endgame. Therefore, Cosmo could be more than an Easter egg. The dog also could've been part of the battle at the Avengers Compound. And since the plot of Hawkeye involves stolen items from the Avengers Compound getting sold at a black-market auction in New York, it makes sense that Cosmo could've tagged along for a ride from the Avengers' headquarters too. There, he meets Kate Bishop and becomes Lucky.

Hawkeye dog

The theory has enough evidence to work. Cosmo has telepathic powers in Marvel's comics, and the dog seems to have an odd understanding of both Clint Barton and Kate Bishop. Additionally, while the comics show the Tracksuit Mafia originally owned Lucky, the Hawkeye series just has the dog show up out of nowhere to protect the items from the Avengers Compound as a Tracksuit Mafia member tries to steal them. Kate Bishop also wears a shirt acknowledging Laika, a dog the Soviet Union sent into space. In Marvel's comics, Cosmo obtains powers after being sent into space.

However, some problems are apparent. For instance, though Kate Bishop's shirt seems like a possible hint that Lucky is Cosmo, it's more of a nod to Marvel's comics, where Kate wears the same shirt. Additionally, Lucky and Cosmo are entirely different characters in Marvel's comics, and the MCU has them played by different dogs. Still, with the Multiverse in play and Marvel constantly inserting Easter eggs and connections into its projects, Lucky's secret Hawkeye identity is a doggone possibility.

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