You write on a piece of parchment, paper, or some other suitable writing material and imbue it with an illusion that lasts for the duration. You can extend the casting time of this spell by 10 minutes for each additional page of hidden you want to write beyond a single page.

To you and any creatures you designate when you cast the spell, any writing that appears on the page writing appears normal, written in your hand, and conveys whatever meaning you intended when you wrote the text. To all others, the writing appears as if it were written in an unknown or magical script that is unintelligible.

Alternatively, you can cause the writing to appear to be an entirely different message, written in a different hand and language; though the language must be one you know. Should the spell be dispelled, the original script and the illusion both disappear. A creature that can see through illusions (such as a creature with truesight) can read the hidden message.

At Higher Level. If you cast this spell using a spell slot of 5th or higher, the duration of the illusion becomes permanent.