As always, I recommend saving in a new slot before trying anything tricky. Then if it doesn't work, you can reload your earlier save and continue from where you left off.

If you don't mind playing most of the level but just want to skip the area with the electric robot, try this:

Play the beginning of the level normally or use the second shortcut to reach the INDUSTRIAL AREA WITH THREE LARGE WATER TANKS.

After shooting the first guard, pull the switch as usual. Now move to the covered button on the right (when facing the switch).

Stand facing the glass cover over the button and touching it.

Then roll...

...and Lara should come up standing inside the glass cover. If it doesn't work the first time, try again, standing a little to the left or right of the center of the cover before rolling.

Turn around on the spot so Lara is facing the button but still standing inside the cover.

You should now be able to press the button even though the cover has not been raised.

Pressing this button summons the second guard. Shoot him as well.

IMPORTANT: Do not use this trick to press the other button on the opposite side of the room (i.e., the one on the left when facing the switch). Doing so closes the door between tank #2 and tank #3, making it impossible to finish the level.

Run down the long hallway, past the entrance to tank #1. (You can now completely bypass tank #1 and the room with the robot.) At the end of the hall, go through the short corridor leading to tank #2, which should be full.

You can swim down to the bottom to get the small medi pack and Uzi clips, but there's no need to pull the underwater lever. Then swim across to the doorway on the left, which leads to tank #3.

Tank #3 should also be full. When you jump into the water, the door on the far side of the pool opens, and another guard comes out. If you climb back onto the step near the entrance, you can shoot him with little or no injury. Now swim across the pool, enter the room the guard came from, and press the button to uncover the second button back in the other room and open the trapdoor at the bottom of tank #3.

Now continue as usual (i.e., monkey swing across the empty tank, return to the room with the switch and buttons, press the button you just uncovered, return to tank #3 and swim down through the open trapdoor). The main walkthrough includes details and more screenshots.

Again, I'm not sure who originally discovered this shortcut. The earliest reference I've seen to the button-cover glitch is on tombraiders.com back in 1998-99.

[Shortcuts Part 2 | Return to the Thames Wharf Walkthrough]