Character Analysis
When we first meet Pesca, he's an energetic, kind-hearted Italian who provides a lot of (now totally dated) hilarity with his butchering of English slang.
"Well! Is four golden guineas a week nothing? My-soul-bless-my-soul! only give it to me—and my boots shall creak like the golden Papa's […]" (1.1.3.34)
And then he goes missing in action for hundreds of pages as the novel descends into serious territory. When Pesca returns again, we're expecting some comic relief and fun scenes with his BFF Walter.
Instead, we get this:
I was over-zealous, in my younger time; I ran the risk of compromising myself and others. For those reasons, I was ordered to emigrate to England, and to wait. I emigrated—I have waited—I wait, still. (3.3.5.49)
Bummer. It turns out that Pesca has a super-secret, super-serious past: he's a member of a dangerous Italian secret society. And it's Pesca's secret society connections that prove to be the downfall of Count Fosco.