Doctor Who - K9 Tales - Invisible Enemy/K9 And Co DVD

INVISIBLE ENEMY is the Tom Baker (fourth doctor) story that introduced robot dog K-9, who would re-appear in the new, revamped series episode 'School Reunion'. Also features 'K9 Tales' - the very first Doctor Who spin-off starring K-9 and Sarah Jane Smith, who would later feature in SARAH JANE ADVENTURES.