Duplicitous Manuscript

From Tasha's Cauldron of Everything, page 126.

Description
Wondrous item, rare (requires attunement by a wizard)

To you, this book is a magical spellbook. To everyone else, the book appears to a volume of verbose romance fiction. As an action, you can change the book's appearance and alter the plot of the romance.

When found, it contains the following spells, which are wizard spells for you while you are attuned to it: Hallucinatory Terrain, Major Image, Mirror Image, Mislead, Nystul's Magic Aura, Phantasmal Force, and Silent Image. It functions as a spellbook for you.

While you are holding the book, you can use it as a spellcasting focus for your wizard spells.

The book has 3 charges, and it regains 1d3 expended charges daily at dawn. You can use the charges in the following ways while holding it:
 * If you spend 1 minute studying the book, you can expend 1 charge to replace one of your prepared wizard spells with a different spell in the book. The new spell must be of the illusion school.
 * When a creature you can see makes an Intelligence (Investigation) check to discern the true nature of an illusion spell you cast, or makes a saving throw against an illusion spell you cast, you can use your reaction and expend 1 charge to impose disadvantage on the roll.