Solitaire, by Alice Oseman, is a realistic fiction novel set in the same universe as most of Oseman's other books. Victoria Spring, more commonly known as Tori, likes blogging and sleeping. She doesn't have a real friend group at school, so she drifts through her life as a character in her brother's and his boyfriend's life. That is, until she discovers a trail of Post-It notes from her locker to an unused computer lab, where she finds a note from Solitaire. She meets Michael Holden, who also is allured by Solitaire's mystery. Together, they attempt to get to the bottom of Solitaire's game but are unprepared for when Solitaire's pranks start going too far.
Solitaire is an easy book to get through: it has short chapters and gets to the point. It has LGBTQ+ and mental health representation and it features a platonic relationship between the Tori and Michael. However, since Solitaire is Alice Oseman's first book, it is lacking in several elements. The characters are difficult to connect with because they don't seem to be fully formed, rather than simply ideas of people. The plot twist regarding Solitaire was apparent from the beginning of the novel, I thought, and could have been put together better. The most compelling part of the book, in my opinion, is that it provides a backstory for some of the characters in Heartstopper. We get to see inside Tori's world, which is similar to Charlie's but is different because she doesn't get the support that Charlie has, despite being his sister.