The officer must have been waiting close by because the marine guard appeared a moment later.

I want you to wait outside with the marine guard.

Over his shoulder he said they would need a marine guard around the clock.

Why you ordered the marine guard away from your quarters.

"That would also explain why you ordered your marine guard away at certain times, to prevent them from seeing what they shouldn't."

She looked around, noting the marine guards at each of the three doors.

A marine guard held the door open for them.

A marine guard held the door open, a polite gesture that stopped short of his eyes.

The marine guards were all dead, as was each and every facility employee.

The last marine guards were picked up on the roof.