is the first episode of the fourth series (season) of the 2017 TV adaptation of The Worst Witch . It originally aired on CBBC in January 2020. Story Overview
The episode begins with Mildred Hubble and her friends returning to Cackle's Academy. After a botched potions experiment, Mildred's appearance is permanently transformed into a girl named . To reverse the spell before sunset, she must find and complete three legendary "impossible" challenges. The Three Challenges
Involves navigating a complex stone template or grid found in an abandoned tower room. [S4E1] The Three Impossibilities
A second riddle or grid that the girls must solve quickly.
Continues to be strict with Mildred, fearing her "chaotic magical abilities" will lead to disaster. is the first episode of the fourth series
The "Three Impossibilities" are a set of tasks left by the very first Miss Cackle. According to legend, completing them undoes any spells cast on that day.
Disguised as "Ursula Catnip" (played by Lydia Page, replacing Bella Ramsey), she struggles with her new identity while trying to fix her mistake. After a botched potions experiment, Mildred's appearance is
This final challenge is originally unreadable and ruined on the stone wall, forcing Mildred to use her ingenuity to figure it out before time runs out. Key Characters & Plot Points