this has happened before, what was it?

so I knew Beltran was going to die just with the way the episode was going. I feel like we've seen this before, or maybe just a trope in other shows and movies? but I really feel like it's happened on grey's before specifically. does anyone remember something else like this where they walk someone through something the whole episode and then that person that seemed "fine" ends up dying? Ugh it's like on the right on the edge of my mind HELP ME or other popular media examples