Diana Wynne Jones' Black Maria is a rather chilling tale. Everyone has an older relative who disapproves of you unless you do what they want and isn't nearly as nice as they pretend to be. But Aunt Maria turns out to be even worse than your average nasty relative. Take the most irritating old lady you can imagine - and then give her evil magic powers, and you've got Aunt Maria, who lives in Cranbury-on-Sea and is only an Aunt by marriage to Chris and Mig's mother. Chris and Mig's father was apparently killed in a car accident, plunging over a cliff on the way to visit his Aunt Maria. Mig and her family go to spend their Easter holiday with their Aunt mainly because Mig's mother feels guilty about Aunt Maria being on her own. However, Aunt Maria is a very prim and proper old lady who's not half as incapable as she likes to pretend, and who makes a point of guilt-tripping people into doing exactly what she wants. Life in Cranbury revolves around Aunt Maria's tea parties, to which only women are invited (the Mrs Urs as Chris and Mig term them). Meanwhile the men of the town act like zombies and the children, who are kept at an orphanage, are like clones.
Mig and her brother Chris hate it in Cranbury, in spite of the sorrowful ghost who appears in Chris's room, but then they start to suspect that magic may be at work in the town, and that Aunt Maria may be at the center of the magic. Then one day Chris annoys Aunt Maria so much that she transforms him into a wolf and it's up to Mig to uncover the magical plot which stretches back over several decades - and is the key to dethroning Aunt Maria.
It's hard enough dealing with elderly, sickly-sweet relatives if they are normal, so imagine what it must be like if they're cold-hearted witches who will turn their own daughters into wolves, as Aunt Maria does to her daughter Naomi (after whom Mig is named, Mig being her preferred nickname). Jones paints a chilling picture of Cranbury as a sort of a "Stepford Wives" situation, except that it's really "Stepford Husbands and Children", who are all slaves to the stifling sweetness of Aunt Maria. Mig is a likeable character, although her rebellious brother Chris is rather more engaging, and I wanted to shake their meek, submissive mother (although she does develop a bit more spunk towards the end of the book). Aunt Maria is frighteningly real: she has strong but outdated opinions - she's horrified at girls wearing trousers, at people eating fish and chips for dinner, and favours boys over girls. But even worse is the fact that she genuinely believes that she is a wonderful person and her magical manipulation of everyone, including Mig and Chris' father is horrifying.