You and the Ghost were captured by an enemy unit to get valuable information from you.

Two days of endless torture, lack of sleep, lack of water.

It ended up with the two of you being thrown into a coffin while you were both unconscious, and then buried alive because you didn't give out any information about your unit.

You came to your senses first, discovering the pitch darkness around and a narrow space, as well as the fact that you were lying on top of the lieutenant.