One of the puzzles you will run into in Resident Evil 2 is the plug puzzle. Check out this Resident Evil 2 monitor room plug puzzle guide to get through it quickly. This one is one of the more difficult puzzles in the game.
Resident Evil 2 Monitor Room Plug Puzzle Guide
For this one you will need all the Chess Plugs, including the one back near the work room. You will have to go through the sewers again to get it before proceeding with the puzzle.
There are two plugs that have pictures on them so place those pieces in the correct spot. Starting at the pawn you then want to place the queen in the middle. After the queen you will place the king in the last slot on that side of the wall. Now the knight wall has the rook in the middle and the bishop in the last spot. This will open the door so you can progress into the next area and find out what is going on.
Check back soon for more Resident Evil 2 guides.