In and , the Third Doctor reunites with Sarah Jane Smith and UNIT for adventures on Earth and beyond, first broadcast on BBC Radio in the 1990s. In , made for LP release in 1976, the Fourth Doctor and Sarah fight alien invasion on present day Earth. The duo return in , for BBC Schools Radio, in which they witness the Earth's early development. is a tongue-in-cheek look at how Susan Foreman's life might have turned out after her adventures with the Doctor, and is a full-throttle adventure for the Sixth Doctor and Peri, first broadcast on BBC Radio in 1985.