Turnip Boy Commits Tax Evasion

In the bunker under your greenhouse. After retrieving the laser pointer bring it to the Mayor. He will lock himself in your greenhouse. Talk to the old lemon and he tells you that there is a secret latch behind the tree. Once inside look through all the rooms as you progress and you should find it on a table and rip it (Tyrant Achievement).

You will also find the book for (Teacher Achievement) and the letter from your dad (Turnipchino Achievement) and of course rip em up.

Here is my achievement guide, for every single achievement in Turnip Boy Commits Tax Evasion.
All of the achievements are ordered and have chapters attached in the video.

For this achievement, you will need to beat most of the game, and get into the bunker below your home.

Make your way through a few rooms, constantly progressing west (left). Once you maneuver a watermelon through portals, and there's a western room to enter, the letter will be in here.