BACK TO WHERE IT ALL BEGAN!

Their tracing an alien signal to modern day Earth, 1985, leads the recently regenerated Doctor and his less than keen assistant Peri to the site where the Time Lord's first onscreen adventures began, concurrent to the TARDIS now able to briefly use its nefarious 'chameleon circuit' (part of producer's John Nathan-Turner's publicity scheme linked to the potential removal of the series Police Box exterior, which was never going to be happen anyway...). 

Attack of the Cybermen gets Colin Baker's era launched properly after the disappointment of the previous season's introductory affair, The Twin Dilemma.

Investigating the new shape of the TARDIS at Totter's Lane.