After the Myth Makers and the teaser episode Mission to the Unknown Doctor Who fans were given a huge 12 part Dalek serial which aimed to capitalise on the early success of the Daleks.
Katarina has joined the Doctor and Steven, Vicki has stayed behind in Troy. Steven is sick and the Doctor tries to find him help. The TARDIS lands on the planet Kembel, the scene of recent Dalek activity. Space security agent Bret Vyon is on the planet desperate to get off to warn Earth about the Dalek's plan, he's even prepared to pinch the TARDIS. The Dalek's have assembled a formidable set of allies ready to conquer the Solar System, even the Guardian on Earth Mavic Chen is part of it.
It's a brilliant opening episode, it starts off really strongly, I love the premise. It feels so big, it feels truly epic. One of my favourite parts to this episode is Katarina, she was beautifully portrayed by Adrienne Hill, such a soft, sweet and innocent performance, a great line when she says 'are these tablets?' her lack of understanding was greatly realised, more so then later characters.
Why did they have to lose this one! It's brilliant. 10/10