How To Open The Underground Red Door In Blue Prince

Are you perplexed by the Underground Red Door in Blue Prince? This particular area is quite well-hidden, and it's more than likely that you'd pass by this location without even noticing that it's there. Our guide discusses how to find this place so you can access what's behind it. Oh, and it goes without saying that this article contains spoilers.

How to open the Underground Red Door in Blue Prince - Underground guide

The Red Door is part of the Underground section of the manor. There are several ways to reach this area, though the fastest method is via the Foundation. That said, there are all sorts of tasks that you need to do first, so you can refer to our Underground guide if you need assistance.

The Red Door in Blue Prince can be found in the Underpass segment. Specifically, you need to get past the giant rotating gear section. Then, when you're walking along the tunnel leading to the Room 46 lever, you need to keep left. There's a very narrow and well-hidden path just before the metal gate.

By default, the Red Door is locked, though you should see a red generator/fusebox next to it, implying that you need to power it up. As it so happens, there's an area inside the manor that actually powers up all sorts of machinery and contraptions. It's none other than the Boiler Room.

During any run, make sure you draft and fully activate the Boiler Room first so you can use the functions in other areas of the manor. As for the Red Door itself, you need to do a few tweaks:

• The switch in the lower section must be flicked to the right.
• The straight tube must be rotated vertically from the gas tank next to it.
• The T-shaped tube must be rotated so that it's connected to the straight tube and the pipe leading to the red fusebox.

Note: As long as the red fusebox in the Boiler Room is lit up, the Red Door in Blue Prince will remain open, even in successive playthroughs. So, you won't need to worry about running out of steps during the same run.

In any case, return to the Underground and go through the Red Door to check the upper section. There are two nooks that you can access, but you still need to rotate the gear control down below. Here's a quick summary:

• The section at the right-hand side has a Mora Jai Color Box. Successfully opening it grants +2 to your allowance permanently. There's also a diagram showing the water levels for a little secret in the Reservoir.
• The section at the left-hand side has a locked gate, and that's what we'll focus on next.

To unlock the gate past the Red Door in Blue Prince, you just need to remember the clues from the 44 pairs of paintings in the manor: "Eight dates crack eight safes."

So, once again, the code is related to a date. It just so happens that you can select up to three letters, and the last one has a number. The solution is: M-A-Y-8. Go ahead and press the button on the side to open the gate.

Inside, you'll find another red letter and a gem, as well as the Treasure Trove blueprint. The Treasure Room grants extra gold, and the trunk that you'll find within has messages that provide more hints for some mid-to-late-game discoveries.

That does it for our guide on how to open the Underground Red Door in Blue Prince. Remember to unlock the other safes as well, such as the ones in the Boudoir, Drafting Studio, Study, and Office. You can also find a couple more in the Shelter and the Drawing Room.