The Red Seal by Natalie Sumner Lincoln

A whodunit from the 1920's.

Twin sisters Helen and Barbara McIntyre give evidence against a burglar who suddenly dies in court, at first seemingly from a heart attack. They discover that the burglar was disguised in court and they recognize him as Helen's fiancée after removing his disguise.

After an autopsy, the burglar is found to have died from poisoning. Was it suicide or murder? The sisters think it was the latter and try to find out who the murderer was. Suspicion shift from the one suspect to the next and a mysterious white envelope with a red wax seal appears and is passed from one person to the other.

What is the content of this envelope, and what role does it play in the whole mystery?

You can view more about this title at the CruGuru website. It is available from Lulu.com. ISBN: 978-1-920265-04-5