Translation scene.
Warren Beatty and Dustin Hoffman may have been huge stars but they flounder trying to execute this type of comedy and also seem miscast in their roles. Writer Elaine May's script is often painfully old fashioned, like one of the old Bob Hope/Bing Crosby "On the Road..." movies minus the subtle charm and wit. And as far as the supporting cast goes, Carol Kane's talents are wasted, Jack Weston feels like a fossil and Isabelle Adjani (Beatty's girlfriend at the time) has zero comedic talent.
Those are some of the nicest excuses I can make for Ishtar, a notorious flop of a movie whose production problems, cost overruns and bad press rival Heaven's Gate and Waterworld.
But to drill down a bit more, another reason Ishtar is so achingly unfunny is due to the performances of the film's co-leads. Beatty has done plenty of comedies but if you examine them (Heaven Can Wait, Bulworth, Shampoo) you'll find the scripts of these films require him to mostly just stumble through looking confused and play off the comedy happening around him. Hoffman also has an iffy track record in the comedy genre, his biggest hit being Tootsie where most of the laughs are found in the performances of Bill Murray and Teri Garr.
Ishtar's story plays like a lesser version of Spies Like Us. Hoffman and Beatty are Chuck and Lyle, a pair of aspiring singer/songwriters who get unwittingly mixed up in North African espionage and a CIA coup attempt. The plot is sometimes confusing; the locations and set pieces are uninspired, and our two bumbling protagonists aren't particularly amusing or sympathetic. (Beatty in particular appears stiff and thoroughly inept at comedy.) As a result, this film just trudges into its third act where we finally come to its one funny scene.
Chuck and Lyle, hiding out in the desert, stumble into a gunrunning deal, so Chuck poses as a local. The gunrunners are suspicious and threaten his life unless he's able to speak to a group of berbers and translate for them. So with a gun in his back, Chuck panics and begins spitting out a ridiculous mix of Spanish, Yiddish, nursery rhymes and just plain old gibberish. Aside from a scene featuring a blind camel repeatedly crashing through a marketplace this is pretty much Ishtar's high water mark. "A hatz foy-a!"... "Kareem Abdul! Kareem Abdul!"
Proof That Even Really Bad Comedies Usually Have At Least One Good Laugh: Dude, Where's My Car Edition
Proof That Even Really Bad Comedies Usually Have At Least One Good Laugh: Coup De Ville Edition