The City Of Death

While leisurely enjoying the city of Paris with Romana, the Doctor feels the effects of time distortion. At the Louvre while admiring the Mona Lisa, he encounters the Countess Scarlioni wearing an alien bracelet used to scan security systems. The Doctor and Romana meet Inspector Duggan, who has been tailing Count Scarlioni for some time; Scarlioni has placed a large number of lost art treasures on the market, and Duggan fears the Scarlionis are looking to steal the Mona Lisa. Though the three are briefly captured by the Countess, the Doctor helps them to escape and explore the Count's mansion, where they discover equipment by Dr. Kerensky to experiment with time, the source of the Doctor's time distortions. They also discover, behind a wall, six exact copies of the Mona Lisa, each painted by Leonardo da Vinci himself.