Theodore Boone is thirteen years old and dreams of swapping his classroom for the courtroom; he thrives on large trials. The largest murder investigation in his city's history is about to commence.

A husband stands trial for the murder of his wife in front of a full courtroom. Is he a deadly criminal or a helpless bystander?

When Theo uncovers a surprise witness with his own troubles to hide, the case takes a sinister turn. Theodore, on the other hand, has been pledged to secrecy, and time is running out.

Will Theo be able to discover a means to bring the killer to justice, or will a guilty man go free?