Four lectures (60 min. each) presented in 1995 by Dr. Thomas R. Cech explain the role of RNA in cellular biology. Dr. Cech also discusses other implications of RNA catalysis. The DVD also includes 3 additional video segments from 2003, 3 hands-on experiment demonstrations, and 3 interactive slideshow features. Lecture 1. Catalysis, chemical and biochemical -- Lecture 2. RNA as an enzyme: discovery, origins of life, and medical possibilities -- Lecture 3. How to accelerate a reaction 100,000,000,000 times using only RNA -- Lecture 4. Life at the end of the chromosome: another RNA machine. Video segments from 2003: Enzymes that are not proteins: the discovery of ribozymes (20 min.) -- Dr. Thomas Cech on becoming a scientist (10 min.) -- NOVA scienceNOW on RNA! (16 min.). Interactive features: New science of RNA interference -- Telomeres ten years after -- Diversity of RNA structures.