I've had the collected volume The New Teen Titans: The Judas Contract sitting on my shelf a long time.
The only other volume I've read was Volume 5 of The New Teen Titans though long forgotten it.
What is the essential reading to preread to understand this trade? I'd prefer to read as little as possible while having enough background to actually enjoy the impact of the Judas Contract.
I know nothing about this storyline so no spoilers please.