Due to a malfunction in the TARDIS, the TARDIS crew materialize on Earth but are only one inch tall. Forester has developed an insecticide that will solve the hunger problems of the Earth but it will also eventually destroy all life. Ian and Barbara witness the murder, by Forester, on a man that would blow the whistle on him. The Doctor, eventually and despite being one inch tall, thwarts Forester by causing an explosion.