F: Swear to yourself that you will return for him
You will not forget this man, you've got to save him from that strange liquid. You swear to yourself you will come back and get him out of there somehow.

In the process you turn the view 90 (NINETY) DEGREES CLOCKWISE and uncover some previously hidden objects! There is 1 (ONE) HARPOON GUN and a NARROW DOOR.

Hang on a second, that door shouldn't be there, there was a window in that room! What's going on here!

F: Observe the lock on the door