Answer
The co-star of Cantinflas in the movie "Around the World in 80 Days" was the renowned British actor, David Niven. Niven's portrayal of Phileas Fogg, the protagonist of the story, perfectly complemented Cantinflas' charismatic performance as Passepartout, Fogg's loyal valet. Their on-screen chemistry and contrasting acting styles made the movie an enduring classic.