it’s the battle of the Five Armies and Thorin, Fili, and Kili went to go kill Azog to get the earth end. Bilbo had gone up to warn Thorin that it was a trap but by that time, it was almost too late.

Bilbo: “there is more Orc’s coming from the north, Thorin. We have to get out of here.”

Thorin: “it was a trap…” starts looking around for Azog but doesn’t see him anywhere.

Kili: running up to them both with Fili. “Thorin…! We checked the area…! It’s all clear!”

Fili: “it seems a little too quiet…”

Thorin: “it’s a trap…! We have to go, now.”