When you have a teammate –
and that teammate is preceding you into a dangerous situation as 'per' the plan –
and you are providing backup…
When that teammate is purposefully putting herself into danger - trying to lure someone into the open…
And you hear gun shots (or the alien equivalent)
Your.
Heart.
Stops.
You have to get there. You HAVE to get there. You don't know, at that point, if the shots are from her weapon or his… if she is bleeding out on the ground or he is… You don't know if you have a teammate anymore or just an enemy who is going to die.
So you move.
Your mind stops,
other than the training.
The training takes over and you just move.
You get in there and you SEE: You see that she is sitting there, holding a weapon on a dead man. And that weapon is shaking just a little.
Then you breathe.