The killer confesses in a letter. Bill and Antony try and wrap their heads around the events of the last few days.

In a town nearby the inquest takes place and everyone gives their statements to the coroner. After the inquest Antony has spark of inspiration and sends Bill on an important errand.

The boys make their way to the pond and just as they thought, Cayley shows up and drops something in. They weave more theories together about what happened to Robert.

At Jalland's, Antony has an interesting conversation with Mrs. Norbury. Antony and Bill prepare for the evening ahead.

Antony returns to the scene of the crime to recall the events just as he had seen them. Then, just as Antony and Bill are investigating the passage with Antony inside, footsteps are heard headed their way.

Antony and Bill investigate the library searching for the secret passage and they go visit the inspector dragging the pond. A bit of information learned from the inspector gives them a new objective for the evening.

Antony and Bill explore the grounds and some theories. As they're discussing the murder, they realize they're not alone and the inspector drags the pond.

Bill gives his account of the events before the murder and Antony demonstrates why he will be an especially good detective and unfurls some of his theories.

Antony and Bill have decided to solve the murder themselves and they may have found their first clue.

There's been a murder and Antony Gillingham has arrived just in time to help discover the body. Now, the master of the house Mark, has gone missing and inspector is on the way.