The Worst Witch All at Sea

The Worst Witch All at Sea is the fourth book in the Worst Witch children's book series by Jill Murphy. It is notable as the only novel that isn't set in Miss Cackle's Academy for Witches, but by the sea instead. This book was published in 1993.

Plot
Mildred Hubble returns to Miss Cackle's Academy for Witches for the Summer Term of her second year. Instead of the usual black-and-grey-checked dresses, Miss Hardbroom persuaded Miss Cackle to change them to plain black. After crash-landing in a pile of snow and meeting up with her best friends, Maud Moonshine and Enid Nightshade, Ethel Hallow appears and tells Mildred that Miss Cackle wants to see her.

When in Miss Cackle's office, Miss Cackle suggests to Mildred that she replaces Tabby. Last term, a third-year witch, Fenella Feverfew, transferred to Miss Pentangle's Academy several mountaintops away and left behind her sleek black cat, Ebony since they have owls at Miss Pentangle's instead of black cats. Down in the kitchens, Mildred reluctantly hands over Tabby to Miss Tapioca (to catch mice) who gives her Ebony in return. A distraught Mildred is too upset to tell either Maud or Enid about it. Miss Hardbroom also announces that Mr Rowan-Webb, the frog-magician whom Mildred had saved from the lilypond the previous term, has invited all the second-years to spend a week's holiday at his castle, Gloom Castle at Grim Cove. Since it is near the ocean, Miss Hardbroom has also sent orders for swimming costumes.

Unable to bear the thought of spending a week-long holiday without Tabby, on the morning before the girls set out for Grim Cove, Mildred sneaks down into the school kitchens and lets Ebony out of his cage and hides Tabby inside. Mildred is slightly late for the departure, but makes it just in time. Along the way, Tabby makes very loud moaning noises, due to his dislike of flying. Luckily, no one suspects that the cat is another cat than Ebony.

When they get to Gloom Castle, they find that it is falling apart: the armchairs in the lounge have springs and lumps and stuffing sticking out of them and there are no proper beds (apart from one, that Ethel Hallow soon claims) other than old sleeping bags, piles of pillows, and what appear to be hospital trolleys. Mildred gets an old sleeping bag exactly under the window, but manages to settle in and divert attention away from Tabby.

Mildred spots a boat attached to a breakwater and decides to hide Tabby in the little cabin on the boat. Mildred successfully manages to hide Tabby into the boat. After a wonderful day of breakfast on the beach and swimming and water activities, Mildred tries to sneak some kippers to Tabby, but Ethel catches Mildred and Mildred pretends to be looking for some mythical treasure on Cat's Head Rock in front of the cove in the boat on the breakwater. As the two head back up the cliff stairs, they witness Miss Hardbroom flying down onto the beach on her broomstick and with her own black cat, Morgana. When on the beach, Morgana runs to the boat and feeds on the kippers that were meant for Tabby. Miss Hardbroom spots both Tabby in the cabin and Morgana eating the fish. She steps onboard the boat to investigate but slips over on one of Morgana's kippers and bangs her head on the little bench and falls unconscious.

When sneaking out to feed Tabby again, Mildred is confronted by Ethel who snidely tells her that she untied the boat from the breakwater and let it drift out to sea. Realising that Tabby was still inside the cabin, Mildred tries to get to the boat. When on the beach, Mildred finds Morgana and Miss Hardbroom's broom inside a small cave. Mildred flies the broom but crashes into the ocean after forgetting that broomsticks don't work very well when they're very close to water. After giving the broom compliments, it flies back up again and drops Mildred onto the boat where she discovers not only Tabby, but Miss Hardbroom's comatose body. Minutes after falling onto the boat, they bump into Cat's Head Rock. Mildred ties the boat onto an odd-looking chunk of rock and falls asleep.

When she awakens, she finds that Maud and Enid have discovered them. They say that everyone was worried sick about Mildred and Miss Hardbroom, who had both gone missing and that several search parties had been sent out. Mildred tells them that there is something strange about the piece of rock the boat is tied onto. They pull at it and find that it is actually the mythical treasure chest. When they get back, Miss Hardbroom is revived and her injured head bandaged, as well as being bed-ridden for the rest of the holiday. The contents of the treasure chest are used to repair all of the damages to Gloom Castle and Mildred is given Tabby back as a reward. Unbeknownst to everyone else, Mr Rowan-Webb gives Mildred a present: a gold necklace of two frogs with emeralds for eyes facing each other and shaking hands. Mildred skips off to enjoy the rest of the holidays with Enid and Maud, feeling like "the luckiest girl in the world instead of the worst witch in the school".

Trivia
- The necklace Mr Rowan-Webb gives Mildred at the end is reminiscent of the events from A Bad Spell for the Worst Witch.

- In this book, the Summer Term dresses are changed from black-and-grey-checked to plain black. In The Worst Witch Strikes Again the Summer Term dresses were black-and-grey-checked. In The Worst Witch to the Rescue the Summer Term dresses are plain black.

- Fenella Feverfew never actually appears in any of the books but she is given a largely increased role in The Worst Witch (TV series) where she is partners with Griselda Blackwood (who appeared briefly in A Bad Spell for the Worst Witch).

- Ethel's only friend, Drusilla Paddock, appears briefly when the girls are choosing their beds where she takes a hospital trolley-like bed that Enid offered to Mildred. Drusilla does not appear again until The Worst Witch to the Rescue where she hides Mildred's pet tortoise up a tree. She, like Fenella Feverfew and Griselda Blackwood, is given a largely increased role in the TV series where she is played by Holly Rivers.

- Miss Pentangle's Academy is mentioned briefly at the beginning by Miss Cackle when talking about Fenella Feverfew leaving Ebony behind. In the next book, The Worst Witch Saves the Day, it is revealed that Miss Hardbroom is good friends with Miss Pentangle (they especially like playing chess together).