be put under a spell

1. To be controlled or afflicted by a magical enchantment. The princess was put under a spell from an evil witch that has kept her asleep for 100 years. A: "Daddy, that frog isn't really a frog, he's a man who's been put under a spell." B: "Oh, of course." Why is the wizard acting so strange all of a sudden? It's like he's been put under a spell too.

2. To be enthralled, captivated, or fascinated (by someone or something), as if by magic. He acts as if he's been put under a spell whenever he's around her. The entire audience was put under a spell as they watched the performance. Every time Professor Drew lectures on Frankenstein, it's like her students have been put under a spell. They're totally riveted by her every word.