Plagiarism and appropriation are hot topics when they appear in the news. A politician copies a section of a speech, a section of music sounds familiar, the plot of a novel follows the same pattern as an older story, a piece of scientific research is attributed to the wrong researcher... The list is endless. Allegations and convictions of such incidents can easily ruin a career and inspire gossip. People report worrying about unconsciously appropriating someone else's work. But why do people plagiarise? How many claims of unconscious plagiarism are truthful? How is plagiarism detected, and what are the outcomes for the perpetrators and victims? Strikingly Similar uncovers the deeper psychology behind this controversial human behavior, as well as a cultural history that is far wider and more interesting than sensationalised news stories.