Tim is working on a series of stories on extra-sensory perception. Martin fears that if he meets the subject of Tim's story, Professor Hammerschlag, the professor will perceive Martin's true identity. When Tim unavoidably brings the professor back the apartment, Martin needs to hide his sensory perception so that the professor can't perceive his thoughts. Unfortunately in the process, Mrs. Brown gets Martin's sensory perception, which in a human causes regression all the way back to babyhood and beyond. The only way for Mrs. Brown to get rid of it is to sneeze it out of her body. To help Mrs. Brown, Martin uses his Martian powers in front of the professor, risking exposure of his identity.
—Huggo