That idea of bonding over thriller series during lunch is spot on. My old team did something like that with crime documentaries, and it totally broke the ice. I mean, we started having these casual debates about who the killer was, and it made everyone way more comfortable around each other. Idk, maybe it's just me, but having that shared thing to talk about besides work really helped us gel. It wasn't even about the shows themselves, but more about having a common interest to laugh and argue over.