What book makes you gleeful with anticipation to continue reading?

I’m reading Trollope’s Barchester Towers on my commute these days, and I’ve just reached a major point when it seems that everything will come to a head. Poor Eleanor! Oh! That wicked Mr. Slope! How will this work out?! It’s delightful in the way that only the Victorians knew how to create. I was quite agitated after this morning’s installment on the bus, and it’s hard switching over to work.

What book is deliciously agitating for you?