Read the full text of Cymbeline Act 1 Scene 5 with a side-by-side translation HERE.
Enter Iachimo, an Italian talking with a Frenchman, a Dutchman, and a Spaniard about everything that's going on with the British royal family. Looks like the news has made it to Rome (where this scene is set).
Posthumus has also made it to Rome, where's he lying low in banishment.
Posthumus introduces himself to the lads, and the conversation quickly turns to—what else?—women.
Iachimo thinks any woman can be seduced. Just name the time and place, and he's there.
But Posthumus disagrees. Not his new bride: she's too virtuous and honest to ever cheat on him.
"Prove it," says Iachimo. He's convinced that there isn't a woman around who could refuse his charms. He'll head on over to England and seduce Imogen. Seriously, this dude is actually suggesting an international seduction plot.
If Iachimo succeeds, he'll take Posthumus's fancy ring (the one from Imogen). He'll also acquire mad bragging rights.
Posthumus is confident enough to take that bet. His terms: if Iachimo strikes out with Imogen, then he'll have to pay Posthumus 10,000 ducats.
As the men leave to write down the terms of their wager with a lawyer, the Frenchmen and Philario talk about what just happened. They let us in on a secret about Iachimo: he's not one to let go of things. Uh-oh.