The Time Contessa is an adventure to Siena, Italy, 500 years into the past and 100 years into the future. Something has gone wrong with an historical timeline, causing a famous painting to disappear from the world's conscious memory, surfacing only in people's dreams. Two members of MIT's Chronology team, Dr. Cassandra Reilly and her colleague Jake, must go to Renaissance Siena to repair the timeline so the artist who painted the portrait of a beautiful woman known as Giuliana will ultimately live to complete it. However, the past holds many pitfalls, both dangerous and romantic, that Cassandra must stay clear of, while trying to prevent Jake falling prey to them as well. The time-travelers' problems follow them to the future, where love takes such a strong hold it becomes impossible to resist, and past adversaries resurface to create new threats.