This is very fun; I love the core gameplay loop of playing conversation cards. It's an interesting take on role-switching, a co-op game where you play both sides, and using card-drawing randomness to make up for the fact that you essentially have infinitely perfect table talk at all times since you are both sides and therefore know the hands on both sides.
The theming is also cool with the nice art and smooth music giving a perfect "secret undercover agent" vibe.
One thing that might've been nice was an improvement on the sort of meta-game of finding which of the four people is the one you're looking for. I don't see much of a reason to leave a conversation and go to another one until you're just kind of done searching one person. Maybe having the characters' decks influence each other, or locking trust progression behind earning trust with another character, or somehow give clues on which of the other people is the actual target person. Just some reason to go back and forth between different conversations.