She felt uneasy, already regretting her decision to meet the man who had sent her those cryptic letters.

They did maintain a voluminous correspondence; for a time he wrote her cryptic letters every Wednesday.

That morning, the millionaire had received a strange, cryptic letter.

But she resumed her meditations on that cryptic letter.

Browne instigated a new investigation by sending a cryptic letter to the authorities in 2000.

But why do these cryptic letters arrive so late?

Meanwhile, unsigned cryptic letters arrived for him in care of Sullivan.

But is the cryptic letter a key to treasure or treason?

Taking hints from seemingly cryptic anonymous letters, John connects the murders to his own military past.

They settled down at the table with pencil and paper, the notebook turned open to the page bearing the cryptic letters.