There is a specific and identifiable literary creature that John Crace has been hunting for twenty-plus years in the Guardian's Digested Read column: the memoir that cannot see its own protagonist. Charles Spencer's Swan Song: Diana, My Sister is a perfect specimen. Crace doesn't need to invent anything. He just needs to hold a mirror at the right angle. The conceit of the digested form is devastatingly simple — compress the book until only its skeleton shows, then let the skeleton dance. What Crace finds inside Spencer's memoir is a man constitutionally incapable of keeping himself off the stage. The eulogy, delivered at Westminster Abbey in 1997, was by any measure a remarkable piece of public oratory. The problem is that Spencer agrees, at length, repeatedly, in print, in a book nominally about his dead sister. Crace's Spencer describes Diana's death and immediately pivots to 'the magnificence of the eulogy I was shortly to deliver to a stunned world.' This is not Crace's invention. It is Crace's excavation. The comic mechanism here is a specific one: the gap between stated intention and revealed character. Spencer writes, according to Crace's rendering, that 'this book is dedicated to William and Harry' and that he is 'doing this for Diana.' But the text keeps drifting, gravitationally, back to the eulogy, back to the Spencer lineage, back to the question of whether the Spencers are of more noble blood than the Windsors. The answer Spencer implies is yes, repeatedly. The reader is left to form their own view. Crace handles the royal family with a lighter touch than the subject invites. His Prince Charles is a vain, slightly dim man-child ('I wish my mum would die... I even have a footman to lay out my electric train set each morning') who exists mainly as a foil for Spencer's self-regard. The Raine Spencer cameo — 'the venomous Raine' — is dispatched in four words, exactly as much oxygen as a digested read can spare for a stepmother. The tabloid press is rendered as a machine that destroyed Diana while Spencer watched from Cape Town, grimly smiling at their discomfort. What Crace is genuinely good at — and this is the craft observation that the column rarely gets credit for — is knowing exactly when to let the subject speak without editorial comment. The line 'And you will be the People's Earl' is presented without a single surrounding joke. It does not need one. The same goes for the exchange where Charles Windsor asks 'Diana who?' three beats after promising everyone will forget her soon. Crace knows the material lands harder when he steps back. The digested read at its best is not parody but compression, and compression is a form of judgment. The product being reviewed is, ultimately, Charles Spencer's judgment about himself. Crace's verdict — rendered through the choice of what to leave in, what to emphasize, and what to end on ('The eulogy which is mine. AAAGH. MAKE THIS STOP.') — is that the judgment is poor. The memoir reportedly charges £28 for the privilege of watching a man discover that grief and self-promotion can coexist more comfortably than either party should be comfortable with. Crace charges nothing extra for the diagnosis.