The following article contains spoilers for Chip 'n Dale: Rescue Rangers, streaming now on Disney+.

Disney+'s animation/live-action hybrid film Chip 'n Dale: Rescue Rangers picks up with the classic Disney duo reuniting for the first time following the end of their Disney Afternoon animated series. A popular offering in Disney's animated output (albeit one mostly overlooked before the film), the original Chip 'n' Dale: Rescue Rangers reinvented its leads as crime-solving sleuths, partnering with adventurer Monterey Jack, inventor Gadget Hackwrench and Zipper, a housefly. Premiering on the Disney Channel for its first season before entering syndication with its second, the series would become the highest-rated children's animated program from 1989 to 1990.

Starring John Mulaney and Andy Samberg, with direction by Samberg's long-time Lonely Island collaborator Akiva Schaffer, 2022's Chip 'n Dale: Rescue Rangers picks up with Chip (Mulaney) living a low-key life as an insurance salesman while Dale (Samberg) trades off his fame making convention appearances alongside other former animated stars. While sharing table-space with Beauty and the Beast's Lumiere, Dale receives a pep-talk from Ugly Sonic, the discarded initial animated incarnation of the character from 2020's Sonic The Hedgehog. This does little for Dale, though, with Ugly Sonic's words undercut by booth mate Tigra of Avengers: United They Stand fame. Amid a sea of references and cameos, the presence of the Marvel Comics heroine is one of the deeper deep cuts in the film, calling back to an obscure short-lived animated series featuring the future box office champions.

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Avengers United They Stand Avengers Assemble

Before headlining 1999's Avengers: United They Stand, the Avengers had enjoyed a steady -- if undistinguished -- history in animation. Making their first cross-media appearance in Grantray-Lawrence's The Marvel Super Heroes in 1966, the team had then-recently cameoed in the second season of the Marvel Action Hour's Fantastic Four. A late-'90s renaissance for the comic title by Kurt Busiek and the late George Perez paved the way for Avengers: United They Stand to become the first proper adaptation and starring role for legendary assemblage. Sort of. The series opted to eschew the traditional "big three" of Captain America, Iron Man and Thor for a roster of secondary heroes led by Ant-Man and the Wasp, including the Vision, Hawkeye, Tigra and Falcon (the latter two making their first appearances outside of comics).

With hit series X-Men and Spider-Man having finished their original broadcast runs during the 1997-1998 season, Avengers: United They Stand was positioned by FOX Kids to be its next big 'Marvel team-up' success. While founding team members Captain America and Iron Man made single-episode appearances, tentative plans for a second season would have seen a full introduction of Thor, who'd been otherwise relegated to a brief appearance in the opening titles. Struggling against upstart programming blocks the Kids WB! and ABC's One Saturday Morning, FOX Kids canceled Avengers: United They Stand after a single season in February 2000.

Outlasting the show was the much better-received tie-in comic by writer Ty Templeton and artist Derec Aucoin. Overseen by long-time Avengers editor Tom Brevoort, the comic dug deeper into the lore of the team and featured characters not seen in the television series. In 2002, artist Mike Deodato Jr. based his interpretation of Tigra in a title starring the character on her animated design. This would be the most recognition Avengers: United They Stand would receive until later animated series Avengers Assemble used several of its unique designs for knock-off movie characters The Revengers in the 2016 episode "Ant-Man Makes It Big." Curiously, most of The Revengers' designs came from an unreleased third wave of the toy line.

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Chip n Dale Rescue Rangers Tigra sells merchandise

Beyond these scattered references and a few international DVD releases, Avengers: United They Stand had been relegated to a footnote in the team's history. That is until Tigra made her grand return in Chip 'n Dale: Rescue Rangers. Seen in a convention booth adorned with promotional art and stills from the series and a few of her original comic book covers, Tigra's appearance reflects her status as the sole member of the animated team yet to cross over into the Marvel Cinematic Universe (even teammate Wonder Man was given Easter egg movie posters in a deleted Guardians of the Galaxy Vol. 2 scene). Portrayed in the film by writer and comedian Liza Cackowski, Tigra has a moment of redemption rescuing Chip and Dale from Seth Rogen's barbarian henchman Bob.

While Chip, Dale and their Rescue Ranger co-stars have found success with a long-overdue reimagining, and animated Marvel project X-Men '97 is due to bring the '90s team back to small screens in 2023, the prospects for Avengers: United They Stand seeing a similar revival are much less optimistic. Nevertheless, as the first series to star the marquee Marvel superhero team, the reference is a fitting nod to a forgotten stab at introducing the world to the Earth's Mightiest Heroes.

Chip 'n Dale: Rescue Rangers and Avengers: United They Stand are currently streaming on Disney+.