The Daleks (airdates May 18 & 25, 1986)
(Part 1 not currently available)
Part 2 Intro: Don't invite a Thal and a Dalek to the same party. Further, don't invite a Dalek to anyparty. Still further, don't hang about with a Dalek at all. They may filch your fluid link, and make it very difficult to continue your existence on "The Dead Planet"... or anywhere else.
(Lionheart gave the movie version of this story the first-episode title, hence the incorrect title above.)
Part 2 "Next Week": Next week, the Doctor attempts to gain control of the TARDIS' faulty guidance system and return the two school teachers to London, 1963... with startling results. They may be observed next Sunday evening at 11 when we approach "The Edge of Destruction."