Enid Nightshade, Millie's friend from Cackles, visits Millie from Primrose Hill (another magic college).
Hearing a plea for help from Dr. Foster, Professor Starfinder leads the students in a location spell and summoning potion to rescue the good doctor. Something appears to go wrong, and they seem to have summoned the wrong person - someone claiming to be a close acquaintance of Dr. Foster.
As a follow-up to The Worst Witch serial, we follow Mildred Hubble in her first year at Weirdsister College, a university for students of magic. Similar to her adventures at Cackle's, Mildred usually messes up, but saves the day in the end. The series has a darker side than The Worst Witch, with evil creatures and a possible doomsday.