have (someone) in (one's) spell
To influence or control someone by being fascinating, enchanting, or seductive. Our son has never acted out like this before. His new friend must have him in her spell. The duchess has countless men in her spell, thanks to her exquisite beauty.
have someone in one's spell
and have someone under one's spellFig. to have enchanted or captivated the attention of someone. She has him in her spell with her grace and beauty. Ken has Karen under his spell.