The first five volumes of the nine volume Complete Thorndyke collection in paperback.

Volume I contains the first three Thorndyke novels, published in 1907, 1911, and 1912, respectively. Set in London during the time that Sherlock Holmes was still in practice, these introduce us to Thorndyke and his world, as well as painting a vivid picture of the London of that era.

The Red Thumb Mark - In which Dr. Jervis encounters his old friend, Dr. Thorndyke. Soon after, they're drawn into a mystery where a man is accused of murder, and his own bloody thumbprint, evidence that cannot be denied, places him absolutely at the scene of the crime. As Thorndyke investigates, it becomes apparent that he is too much of a threat and must be removed.

The Eye of Osiris - Wherein a man vanishes and is presumed dead. But from where and when exactly did he disappear? That is the initial question, but by the end it's much more complex, with one of the most unique solutions in mystery history!

The Mystery of 31 New Inn - Dr. Jervis is summoned at night by closed carriage to treat a gravely ill patient - but is he simply sick or being murdered? His suspicions continue to grow, and Thorndyke provides a unique solution. But that's only half, as the two also become involved in an unusual death related to a young man's inheritance.

Volume II contains roughly the first half of the Thorndyke Short Stories. In all, there are over forty Thorndyke short stories, spread over six books. This volume contains the fifteen short stories from the first three, John Thorndyke's Cases, The Singing Bone, and The Great Portrait Mystery.

Some of the stories in this book are especially famous, as they were the first use of the "inverted" mystery, in which the criminal (and how he did it) are identified from the first, and the second half of the narrative shows how Thorndyke solves it, in spite of the criminal's every effort. (The "inverted" crime story was later used to great success by Columbo, as well as other detectives.)

In addition to these fifteen stories, this book also contains a couple of Apocrypal Thorndyke tales:

The original novella of "31, New Inn" from 1905, which became The Mystery of 31 New Inn, the third Thorndyke novel from 1912. This is the doctor's true first appearance - written and published several years before the appearance of The Red Thumb Mark (1907), which is commonly believed to be Thorndyke's first published adventure; and
"The Dead Hand" (1912), which later became the revised and expanded Thorndyke novel The Shadow of the Wolf (1925).

Volume III contains the remaining half of the Thorndyke Short Stories. These, along with the contents of 2018’s Volume II (with the first half of the short stories and a few rare Apocryphal items), presents the complete short Thorndyke mysteries for a new generation.

In all, there are over forty Thorndyke short stories, spread over six books. This volume contains all twenty-five stories from the final three collections, Dr. Thorndyke’s Casebook, The Puzzle Lock, and The Magic Casket.

Some of the stories in this book are especially famous, as Freeman was the first to use the “inverted” mystery, in which the criminal (and how he did it) are identified during the first half of the story, and the second half of the narrative shows how Thorndyke solves it, in spite of the criminal’s every effort. (The “inverted” crime story was later used to great success by Columbo, as well as other detectives.)

Volume IV contains the fourth, fifth, and sixth Thorndyke novels, published in 1914, 1922, and 1923, respectively. Covering different periods in the doctor’s career, each of these shows Thorndyke’s skills at their finest.

A Silent Witness – When a young doctor finds a body that almost immediately vanishes, he’s drawn into a dangerous plot which endangers his own life, and eventually leads the murderer to strike at Thorndyke’s own door.
Helen Vardon’s Confession – In this unusual adventure, Helen Vardon tells her own story, in which her future is nearly stolen from her, and she is set on a path leading to her ultimate destruction – unless Dr. Thorndyke can save her.
The Cat’s Eye – An inheritance with ties to the Jacobite Rising of 1745 sets in motion a series of events that threatens not only Thorndyke’s friends, but his own life as well.

Volume V contains the seventh, eighth, and ninth full-length Thorndyke adventures, published in 1924, 1925, and 1926, respectively. With each subsequent narrative, Thorndyke’s skills and abilities grown and amaze.

The Mystery of Angelina Frood – In which a doctor, newly arrived in Rochester, falls in love with Angelina Frood. When she abruptly vanishes, only Thorndyke’s skills can discover the truth in a most surprising manner.
The Shadow of the Wolf – Two men depart on a boat, but only one returns. What follows is one of the best examples of Thorndyke’s method as he plays a deadly game with the player on the other side.
The D’Arblay Mystery – A young doctor discovers a body in a pond. Was it an accident, or suicide, or murder? One thing is certain – the danger has not ended with just one death.

The full collection is here - Thorndyke Collection