Shelby's driving compulsion was to avenge her dead parents, whose catamaran was torpedoed by a Russian submarine while they were on vacation.
I'm thinking "while they were on vacation" might be a little too far removed from "parents." I don't know, though. Does it work as is?
I'm not going to try to "fix" it - that's the writer's job - but it doesn't work
for me because I feel like I'm getting too many hugely important facts in one breath, as it were. So I skim all of them and end up not caring that Shelby has a driving ambition, that that revolves around an act of revenge, that her parents have been ?murdered, that their boat was torpedoed or why, or who torpedoed it - or even where Shelby's parents went on their last vacation together and if they feel it was worth the fare, all things considered.
Unless you were writing (now that I think of it) a gloriously straight-faced massive satire of a specific genre novel, it's too much, too quickly, and too early. And much too casually.