Sadhana Shivdasani, known mononymously as Sadhana, was an Indian actress who worked in Hindi films. Regarded among the most popular actresses of Hindi Cinema, Sadhana was noted for her exquisite beauty and trend-setting fashion statements. She was popularly known as "The Mystery Girl" for her stint as the "mystery girl" in the suspense thriller trilogy films directed by Raj Khosla during the mid 1960s.