In the 26th century, the three crewmembers of the space yacht Heliotrope Bouquet II depart Soarpath Junction, only to become caught in the middle of a space battle between Daleks and Cybermen. They escape, but the ship is badly damaged. While making their way to a safe harbour, a Cyber-Leader forces them to return to the battle so he can destroy the Dalek ship. They succeed in tricking the Cyberman, destroy him, and resume course away from the battle.
At this point in time, the last contact with the Daleks and Cybermen was so long ago that some people no longer believe in them. In TV: The Space Museum, Vicki (who is from 2493) didn't know what a Dalek looked like until she saw one, and in TV: The Tomb of the Cybermen (set in the previous century) the Cybermen are believed to have died out centuries ago.