And that Linx is using an optical hypnotism device to control the 12 scientists whom he kidnapped using the Osmic Projector from the 20th century. Rubeish is unaffected by his poor vision and is able to help the doctor find a way to warn Sir Edward of Essex of Irongrons plans-to use the firearms Linx has supplied him with to rob Sir Edward and his court as a favor for using Irongrons castle as a base from which to repair his ship with his human slave labor. Sarah finaly learns of the doctors benevolent intention when both meet before Sir Edward and,with his help the doctor and Sarah hatch a plot to foil Linx and Irongron,and return the enslaved scientists to their time. While collecting food for the starving scientists,Sarah ends up a cook. She puts a sleeping potion into the food being prepared for Igornron's men-which enambles one of Sir Edwards men Hal to help her and Doctor get into Linx's work chamber to destroy his ship after Rubeish has used the Osmic Projector to send the other scientists back to where they came from and kill Linx in his ship before it can depart. After thanking Hal for his assistance,he watches as Sarah Jane and the doctor depart in the TARDIS.
This is a very important third doctor story. It is the very first to use the second third doctor opening-featuring the Doctor Who logo used throughout Tom Baker's 70's era run on the show as well. Right off the bat Elizabeth Sladen's introduction as Sarah Jane Smith is a memorable one. Her character is at the very heart of this story in face. Through the cruelty of the Sontaran Linx-nearly starving his captures to death as well as the sexism and excessive violence of Earth's past Sarah Jane comes to fully understand the nature of the woman's liberation movement she is so much a part of. This of course leads her to trust the doctor, who fast comes to respect her as a complete equal. Throughout the story she is of equal assistance in solving the time meddling of Linx,offering guns to primitive human criminals centuries before they were ready. And despite his affable eccentricity, Professor Rubeish proves himself just as capable and helpful as a one off companion. This is also the first story where the doctor reveals the name of his home world Galifrey. As well as some witty moments where,in response to a slave Wench telling her that woman's place will never change among men,Sarah Jane responds "That's subservient rubbish! You talk as if it is the middle ages!",and of course that is exactly where she is in this story.