The Impostor

by Sophie McKenzie

The arrival of a secret sibling tears a family apart. But is she who she claims to be?


Wealthy business tycoon Nathaniel Carson dies, leaving behind a vast fortune to his family. The Carsons host a dinner to celebrate what would have been his 79th birthday – only to have an unexpected guest arrive.

Mia claims to be Nathaniel’s youngest child, the product of an affair. Unassuming, likeable and seemingly desperate to connect with the family she did not know existed until a few weeks ago, Cassie Carson welcomes her with open arms. But not everyone is quite so accepting of the new addition.

When a series of concerning coincidences emerge and a family member is killed in suspicious circumstances, even Cassie begins to doubt her new sister.

The more Cassie unearths, the more terrified she becomes. Who really is Mia? And what lengths will she go to in order to get her hands on the family fortune?

A tense psychological thriller full of twists and turns. Perfect for fans of Gillian McAllister and Lisa Jewell.

Genres: Thriller

Kindle Edition

Expected publication November 17, 2026

About the author

Hey there! Welcome to my Goodreads page where you can keep up with all my stories - both the ones that are already published and the works in progress!!

I write mostly teen thrillers - plus some teen romance, books for younger children and four adult psychological thrillers.

I'm really excited right now because of...

Boy, Missing, my £1 book for World Book Day and Truth or Dare, my new teen thriller. (UK)


For more info on these and my other books, check out my website: www.sophiemckenziebooks.com

Reviews

[Ashleigh Davidson · Rating 1 out of 5]

This was an absolute crock of shite 🤣

[pineapple · Rating 3 out of 5]

i’m baffled with this whole story and the chapter before the ending. firstly, the characters are so annoying, they are like rich kids that are gonna inherit a lot of money, yet they still want more. then they get suspicious of mia, but you have the kind female lead who tries to be close with her new sister, but at the same time, get jealous because she’s skinny… and not to mention her gullible husband, rob.


SPOILER!!











he’s the best husband anyone can ask for. instead of figuring out why his wife is thinking like this, he decides to side with mia. whenever cassie tells him her suspicions, he would get all defensive and tell her how mia is the nicest person on earth and how her story about abusive people. and the worst part, siding with mia instead of his wife. instead of staying at his mother’s place, once mia calls while sobbing, he would be the hero and come save her, without informing his wife because ‘oh i knew you will be angry.’ tell me which sane person wouldn’t be mad that your husband is protecting another woman and not telling you. and obviously the sprinkle on top is that he would ask mia to take care of his child while he’s working INSTEAD OF HIS WIFE (because pfft we getting her a new mom obviously) and not telling his wife about it!! AND THE BEST PART, WHEN HIS WIFE SHOWS PROOF THAT MIA HAS BEEN LYING, WHY DID IT DO? HE WENT STRAIGHT TO HER TO TELL HER ABOUT WHAT HIS WIFE TOLD HIM. girl, honestly if he’s my husband, i don’t want him no more. the ending should be a lie or maybe cassie is such a saint that she would accept such person as her husband. someone who believes other people as long as they shed some tears instead of someone he married!!


also the second last chapter was so underwhelming because why did tommy decides to be a “good” person and sacrifice himself. like bro did so much, killed a nurse and his half brother, injured his half sister, blame everything on his other half brother. just for him to idk see his niece cry and decides to protect them… like make it make sense. also, the ending where they gonna sell the company?! like is it just me, how about the company legacy… imagine working so hard just for your children to sell your company…

[Stephanie Hartley · Rating 3 out of 5]

**3.5 stars**

I remember reading and loving Girl, Missing as a teenager, so I was delighted to receive this in a book subscription box and seeing it was written by the same author. The book was full of twists and turns, and totally reminded me of succession, so if you liked that you'll probably enjoy this.

When Nathaniel Carson dies, his inheritance is set to be split between his four siblings. But when a fifth surprise child turns up out of nowhere one night, the family is rocked to the core. Suspicions abound, and when a further member of the Carson family winds up dead, things only get more intense.

I absolutely tore through this - it was a really gripping twisty thriller. It just felt a little bit too like succession for me, and I annoyingly guessed who was the culprit behind things quite early on. There were definitely some twists I didn't expect, and I got totally wrapped up in the read, but it wasn't the best thriller I've ever read.

[Vikash Kumar · Rating 4 out of 5]

I liked the book. The writing stayed faithfully within the protagonist’s perspective, which made every emotion feel authentic.
Tommy’s comment about Mia’s blonde hair even though he didn’t see her at the dinner was a definite tell for me. I was waiting for a reference to it in the end.
Too many twists at the climax was a little overwhelming. But rest was good.

[Elese Palmer · Rating 4 out of 5]

A witty and engaging piece of work but the version I own has missed a few vital edits. Very distracting. Otherwise a good plot and an unexpected twist for the finale showdown!

[Emma Cornthwaite]

Good writing. Unexpected end. Nice easy reading

[Vicki Mustard · Rating 1 out of 5]

Dreadful - poor writing, 2 dimensional characters and a ridiculous plot, came as part of a monthly book club read - don’t bother!