The Rainmaker’s Milo Callaghan, John Slattery Reveal How They Brought the Iconic Novel to Life

In fact, it leads to Rudy facing off against Leo—and Sarah—as he attempts to hold the hospital they represent accountable after the death of a patient in its care. With that, the cast spent a lot of time immersing themselves in the “quite rigorous legal academia,” as Callaghan put it.

Crucially, however, viewers don’t need three years of law school to unpack all the rapid-fire legalese—in large part thanks to Slattery’s character.

“Leo’s function was also to sort of explain,” the Mad Men alum noted. “Somebody would say something, and I, as Leo, would say, ‘Well, what he actually means is, you know, blah, blah, blah’ to the jury and try to win them over that way. Like he’s trying to be highfalutin here, but what he’s really saying is to the audience as well.”