I went to Fort Dawnguard for the first time and Agmaer and me walked up to the gates.

I decided to talk to Durak and Agmaer stood by waiting for me.

While I'm talking to Durak I hear the combat music start up so I exit the speech and turn to see Agmaer get slashed to the ground by a Boethiah cultist.

I didn't have any weapons on me except the crossbow that I had just gotten.

Durak rushes in and starts duking it out with the Boe cultist but get his butt handed to him.

Then the Boe cultist runs after me but Celann comes rushing in and cuts him down right infront of me.

As Celann is walking away from me with a look of anger on his face, he says "Go see Isran" in a pissed off tone.

Hah. I love it when stuff like this happens.

Side note..this is one of the many reasons essential NPC's are necessary lol