You're on a sinking ship full of objects to grab. Some things disappear as the ship sinks; others require a bit of puzzle solving. You can't grab everything. So the idea is to maximise your profit by grabbing those things that will give you the highest yield in the shortest time. It's actually more fun than it sounds.
The fun aspect comes almost entirely from the titular Captain Verdeterre. This is the rat, literally a rat, who is the captain of the ship and who follows you around. He is ... a feckless, affectionate, self-important rascal, keen to remind you that he is your boss yet so helpless without you. It's a very fine and difficult line between the verbs "to abuse" and "to amuse", and Verdeterre somehow manages it. That is impressive. I think there are shades here of Bertie Wooster, if Bertie Wooster were a better swordsman. And a rat.
I did appreciate the different endings based on the amount of loot gained from the venture. From what I've seen, things generally work out fairly well. Verdeterre is a fairly indulgent boss, even if he doesn't really give you the credit you deserve. I don't know if I managed to max out my score, but I think my favourite line comes from the best ending I'd gotten thus far. After thanking you for making him so incredibly rich: "Yeah. Yes," he says. "I am going to buy a polar bear." Which, I believe, says everything that needs to be said about the sort of person (rat!) Captain Verdeterre is.
Smoked salmon Benedict and strong coffee with extra cream. Mm, decadent.