The early fourth Doctor episodes titled Arc of Space contains the following things:

• A working sonic screwdriver (Didn’t know it made an appearance so early).
• An ortopcy of an rubber space bug.
• Green painted bubblewrap with som yarn glued ontop as a larva.
• Not a single reference to PIGS IN SPACE. This was a major, and I mean major, disappointment.
• Lots and lots of white space walls.