Incognito Spell by kutto at Mod The Sims

This mod adds a new “Incognito” spell that allows Spellcasters to equip a magical disguise. Play pranks on your friends (or enemies) without any hard feelings. Engage in a steamy affair without your Sim’s significant other finding out. The possibilities are endless when there aren’t any consequences!
This spell belongs to the Mischief school of magic and can be learned in all the usual ways. Spellcasters need to be at least rank 3 (Adept) in order to learn it.