read someone like an open book, to

read (one) like an open book

To analyze and understand one very easily and intuitively, especially one's emotions, motivations, etc. I can read you like an open book, and I can tell that something's wrong, so please tell me what it is. I tried to hide how sad I felt while I was in front of my parents, but they read me like an open book.
See also: an, book, like, open, read
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.

read someone like an open book, to

To discern someone’s thoughts with great accuracy. The analogy of a guileless person to an open book was made by Shakespeare. “Read o’er the volume of young Paris’ face,” he wrote in Romeo and Juliet (1.3), and again, “O, like a book of sport thou’lt read me o’er,” in Troilus and Cressida (4.5). A closely related turn of phrase is to read someone’s mind, which dates from the late nineteenth century.
See also: an, like, open, read, someone, to
The Dictionary of Clichés by Christine Ammer Copyright © 2013 by Christine Ammer
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