Sheldon tells Penny that he is still interested in String Theory because it is elegant. He gives a brief explanation of it and states that scientists have been working on it for decades.

Ben DeLaney describes virtual reality and explains the fundamentals of how it works. He showcases several virtual reality applications and provides use cases for the technology to show how powerful it can be. While this clip depicts some outdated technology, the fundamentals of how virtual reality works are still relevant today.

Grover explains and demonstrates the concept of force by pulling a rope. He also illustrates how to influence force by inviting friends to pull the rope with him.

The group escapes from hepatitis B and enters Alveoli Forest, where they encounter the bronchial tubes, alveoli, and the disease, tuberculosis. Dr. Bloom explains that the human has latent tuberculosis, as the disease is usually found in many people's lungs but is not active. He changes his opinion, however, when he sees that tuberculosis bacteria has escaped from its inactive state.

Biff and his friends bully George McFly into doing their homework for them. After the bullies leave the cafe, Goldie encourages George to stand up for himself.