Young Mary follows a mysterious cat into the nearby forest and discovers an old broomstick and the strange Fly-by-Night flower, a rare plant that blossoms once every seven years. Together, the flower and the broomstick whisk Mary above the clouds, and far away to Endor College — a school of magic run by headmistress Madam Mumblechook and the brilliant Doctor Dee. But there are terrible things happening at the school, and when Mary tells a lie, she must risk her life to try and set things right.
https://en.wikipedia.org/wiki/Mary_and_the_Witch%27s_Flower