[6] An Unearthly Child (Susan/Barbara/Ian)
[6] The Rescue (Vicki)
[6] The Chase (Steven) 
[1] The Myth Makers (Katarina) 
[5] The Daleks’ Master Plan (Sara)
[5] The Ark (Dodo)
[5] The War Machines (Polly/Ben)
[5] The Higlanders (Jamie)
[5] The Evil of the Daleks (Victoria)
[3] The Wheel in Space (Zoe)
[8] Spearhead from Space (Liz)
[5] Terror of the Autons (Jo)
[5] The Time Warrior (Sarah Jane)
[5] Robot (Harry)
[5] The Face of Evil (Leela)
[3] The Invisible Enemy (K9)
[6] The Ribos Operation (Romana I)
[5] Destiny of the Daleks (Romana II)
[5] Full Circle (Adric)
[5] Logopolis (Nyssa/Tegan)
[5] Mawdryn Undead (Turlough)
[1] The King’s Demons (Kamelion)
[3] The Five Doctors (The Brigadier)
[5] Planet of Fire (Peri)
[5] Terror of the Vervoids (Mel)
[6] Dragonfire (Ace)
[3] Doctor Who - The Movie (Grace)
I love the Myth Makers but as an introduction for the brand new long term companion 
Katarina, it leaves a lot to be desired.
I don’t really agree with this, Steven is prominently featured in the end of the Chase - hiding on Mechanus from Daleks and Mechonoids with only his beloved Hi-fi for company.
I am not the biggest fan of the Chase but for introducing Steven it is really great 