Patricia Wentworth 
Weekend with Death [EPUB ebook] 

While waiting for a train connection, Sarah Marlowe is drawn into a conversation with an elderly woman named Emily who is also traveling alone. She tells Sarah an incredible tale of being entrusted with a package by a stranger dying of a stab wound. Soon afterward, on the train to London, Sarah discovers the same package in her own handbag. The next day, she learns Emily has been murdered.
Beloved crime writer Patricia Wentworth fills us with romance, adventure, and gothic intrigue in this exciting thriller.