The premise of The Immortalists was amazing, the story of a family fighting against their fate and death itself. However, the story didn't really deliver on that front, I kind of ended up feeling like the science-fiction/fantasy aspects of the story had been rather glossed over. However, the relationships and bonds between the characters were deep and well-written, which brought the story back up to four stars from what might have been a two or a three.
Out of the four main characters, Varya was my favorite by far. Her ambition and drive was just so fascinating to read about, and since all the siblings knew when they would die, it was almost frustrating to me that she was the only one who had gone into longevity research. Daniel seemed slightly flat to me, but I liked the two younger siblings, Klara and Simon.
Overall, it wasn't what I had expected from the summary, but it was still an engaging story that caught my attention.