The Doctor Who Production Diary: 1970

January
3 Debut broadcast of Spearhead From Space episode one on BBC1, the first colour episode of Doctor Who Spearhead From Space
5 Caroline John is contracted for two serials beginning with The Ambassadors Of Death, although Barry Letts is unhappy with the character and will decide to replace her for Season Eight Liz
Shaw
5 Recording for The Silurians takes place in BBC Television Centre Studio 1 The Silurians
9 Don Houghton is commissioned to write Inferno Inferno
10 Debut broadcast of Spearhead From Space episode two on BBC1 Spearhead From Space
12 Recording for The Silurians takes place in BBC Television Centre Studio 1 The Silurians
17 Debut broadcast of Spearhead From Space episode three on BBC1 Spearhead From Space
19 Recording for The Silurians takes place in BBC Television Centre Studio 8 The Silurians
23 Location filming for The Ambassadors Of Death takes place in Little Marlow, Buckinghamshire and Spade Oak, Buckinghamshire The Ambassadors Of Death
24 Debut broadcast of Spearhead From Space episode four on BBC1 Spearhead From Space
26 Recording for The Silurians takes place in BBC Television Centre Studio 8 The Silurians
26 Location filming for The Ambassadors Of Death takes place in Southall, Middlesex The Ambassadors Of Death
27 Location filming for The Ambassadors Of Death takes place in Southall, Middlesex and London The Ambassadors Of Death
28 Location filming for The Ambassadors Of Death takes place in London The Ambassadors Of Death
29 Location filming for The Ambassadors Of Death takes place in High Wycombe, Buckinghamshire and Marlow, Buckinghamshire The Ambassadors Of Death
30 Location filming for The Ambassadors Of Death takes place in Aldershot, Hampshire The Ambassadors Of Death
31 Debut broadcast of The Silurians episode one on BBC1 The Silurians
31 Location filming for The Ambassadors Of Death takes place in Aldershot, Hampshire The Ambassadors Of Death

February
2 Location filming for The Ambassadors Of Death takes place in Beacon Hill, Hampshire The Ambassadors Of Death
3 Location filming for The Ambassadors Of Death takes place in Northfleet, Kent The Ambassadors Of Death
4 Location filming for The Ambassadors Of Death takes place in Northfleet, Kent The Ambassadors Of Death
7 Debut broadcast of The Silurians episode two on BBC1 The Silurians
13 Recording for The Ambassadors Of Death takes in BBC Television Centre Studio 3 The Ambassadors Of Death
14 Debut broadcast of The Silurians episode three on BBC1 The Silurians
20 Recording for The Ambassadors Of Death takes in BBC Television Centre Studio 3 The Ambassadors Of Death
21 Debut broadcast of The Silurians episode four on BBC1 The Silurians
23 John Levene is contracted for Inferno Sergeant
John Benton
27 Recording for The Ambassadors Of Death takes in BBC Television Centre Studio 3 The Ambassadors Of Death
28 Debut broadcast of The Silurians episode five on BBC1 The Silurians
late
Feb
Head of Serials Ronnie Marsh confirms that Doctor Who will return for Season Eight The Third Doctor

March
5 The Treaty on the Non-Proliferation of Nuclear Weapons takes effect
6 Recording for The Ambassadors Of Death takes in BBC Television Centre Studio 3 The Ambassadors Of Death
7 Debut broadcast of The Silurians episode six on BBC1 The Silurians
9 Jon Pertwee is contracted for the twenty-five episodes of Season Eight The Third Doctor
13 Recording for The Ambassadors Of Death takes in BBC Television Centre Studio 3 The Ambassadors Of Death
14 Debut broadcast of The Silurians episode seven on BBC1 The Silurians
20 Recording for The Ambassadors Of Death takes in BBC Television Centre Studio 4 The Ambassadors Of Death
21 Debut broadcast of The Ambassadors Of Death episode one on BBC1 The Ambassadors Of Death
23 Roger Delgado is contracted to play the Master, the Doctor's new Time Lord arch-nemesis, in Season Eight The
Master
27 Recording for The Ambassadors Of Death takes in BBC Television Centre Studio 1 The Ambassadors Of Death
28 Debut broadcast of The Ambassadors Of Death episode two on BBC1 The Ambassadors Of Death
31 Location filming for Inferno takes place in Strood, Kent Inferno

April
1 Location filming for Inferno takes place in Strood, Kent Inferno
2 Location filming for Inferno takes place in Strood, Kent Inferno
3 Location filming for Inferno takes place in Strood, Kent Inferno
4 Debut broadcast of The Ambassadors Of Death episode three on BBC1 The Ambassadors Of Death
6 Bob Baker and Dave Martin deliver their script for episode one of “The Gift”; it is rejected, but the writers are offered the opportunity to revise the storyline The Claws Of Axos
6 Filming for Inferno takes place at the Ealing Television Film Studios Inferno
7 Filming for Inferno takes place at the Ealing Television Film Studios Inferno
8 Nicholas Courtney is contracted for Season Eight Brigadier Alistair Gordon Lethbridge-Stewart
8 Filming for Inferno takes place at the Ealing Television Film Studios Inferno
11 Debut broadcast of The Ambassadors Of Death episode four on BBC1 The Ambassadors Of Death
13 An oxygen tank explodes aboard Apollo 13 while it is en route to the Moon; the craft is able to return to Earth four days later
18 Debut broadcast of The Ambassadors Of Death episode five on BBC1 The Ambassadors Of Death
22 The first Earth Day is celebrated
24 Recording for Inferno takes place in BBC Television Centre Studio 3 Inferno
25 Debut broadcast of The Ambassadors Of Death episode six on BBC1 The Ambassadors Of Death
27 Director Douglas Camfield collapses during rehearsals for Inferno as a result of stress and a heart condition; Barry Letts assumes his duties for the remainder of the serial's production Inferno
28 Robert Holmes is commissioned to provide a storyline for Terror Of The Autons Terror Of The Autons

May
2 Debut broadcast of The Ambassadors Of Death episode seven on BBC1 The Ambassadors Of Death
4 Four Kent State students are killed by National Guardsmen at a protest against the American incursion into Cambodia
7 Recording for Inferno takes place in BBC Television Centre Studio 3 Inferno
8 Recording for Inferno takes place in BBC Television Centre Studio 3 Inferno
9 Debut broadcast of Inferno episode one on BBC1 Inferno
16 Debut broadcast of Inferno episode two on BBC1 Inferno
21 Recording for Inferno takes place in BBC Television Centre Studio 6 Inferno
22 Recording for Inferno takes place in BBC Television Centre Studio 6 Inferno
23 Debut broadcast of Inferno episode three on BBC1 Inferno
29 Recording for Inferno takes place in BBC Television Centre Studio 3; Caroline John leaves Doctor Who Inferno
30 Debut broadcast of Inferno episode four on BBC1 Inferno

June
6 Debut broadcast of Inferno episode five on BBC1 Inferno
12 Robert Holmes is commissioned to write Terror Of The Autons Terror Of The Autons
13 Debut broadcast of Inferno episode six on BBC1 Inferno
20 Debut broadcast of Inferno episode seven on BBC1 Inferno
22 John Levene is contracted for eighteen episodes of Season Eight Sergeant
John Benton
24 Charlotte and Dennis Plimmer are commissioned to write “The Cerebroids” The Third Doctor
29 Don Houghton is commissioned to provide a storyline for The Mind Of Evil The Mind Of Evil
29 Malcolm Hulke is commissioned to provide a storyline for Colony In Space Colony In Space
29 Charlotte and Dennis Plimmer's “The Cerebroids” is abandoned The Third Doctor
late
Jun
Ian Marter is cast as the new character of UNIT Captain Mike Yates Captain 
Mike Yates

July
1 After Ian Marter refuses the role of Captain Yates due to other commitments, Richard Franklin is contracted to play the character in Season Eight Captain 
Mike Yates
3 Katy Manning is contracted to play new companion Jo Grant in at least twenty episodes of Season Eight Jo 
Grant
10 John Simm (the Master) is born The
Master

August
6 Don Houghton is commissioned to write The Mind Of Evil The Mind Of Evil

September
11 Bob Baker and Dave Martin are commissioned to write a new episode one for what was originally “The Gift”, and will now become The Claws Of Axos The Claws Of Axos
15 Malcolm Hulke is commissioned to write Colony In Space Colony In Space
17 Location filming for Terror Of The Autons takes place in Chalfont St Peter, Buckinghamshire; Chalfont St Giles, Buckinghamshire; and London; Richard Franklin joins the regular cast of Doctor Who Terror Of The Autons
18 Location filming for Terror Of The Autons takes place in London; Katy Manning and Roger Delgado join the regular cast of Doctor Who Terror Of The Autons
21 Location filming for Terror Of The Autons takes place in Dunstable, Bedfordshire Terror Of The Autons
22 Location filming for Terror Of The Autons takes place in Caddington, Bedfordshire Terror Of The Autons
23 Location filming for Terror Of The Autons takes place in Caddington, Bedfordshire and Dunstable, Bedfordshire Terror Of The Autons
24 A photocall is held to introduce Katy Manning as new companion Jo Grant Jo 
Grant

October
9 Recording for Terror Of The Autons takes place in BBC Television Centre Studio 8 Terror Of The Autons
10 Recording for Terror Of The Autons takes place in BBC Television Centre Studio 8 Terror Of The Autons
16 Canadian Prime Minister Pierre Trudeau effectively declares martial law following political kidnappings committed by the militant Front de Libération du Québec
18 Bob Baker and Dave Martin are commissioned to write episode two of The Claws Of Axos The Claws Of Axos
19 Bill Strutton is commissioned to write a storyline for “The Mega” The Third Doctor
23 Recording for Terror Of The Autons takes place in BBC Television Centre Studio 6 Terror Of The Autons
24 Recording for Terror Of The Autons takes place in BBC Television Centre Studio 6 Terror Of The Autons
26 Location filming for The Mind Of Evil takes place in Dover, Kent The Mind Of Evil
27 Location filming for The Mind Of Evil takes place in Dover, Kent The Mind Of Evil
28 Location filming for The Mind Of Evil takes place in Dover, Kent and Whitfield, Kent The Mind Of Evil
29 Bob Baker and Dave Martin are commissioned to write episodes three and four of The Claws Of Axos The Claws Of Axos
29 Location filming for The Mind Of Evil takes place in Manston, Kent The Mind Of Evil
30 Location filming for The Mind Of Evil takes place in Dover, Kent and Pineham, Kent The Mind Of Evil
31 Location filming for The Mind Of Evil takes place in Dover, Kent The Mind Of Evil

November
2 Location filming for The Mind Of Evil takes place in London The Mind Of Evil
3 Location filming for The Mind Of Evil takes place in London The Mind Of Evil
9 Ian Stuart Black is commissioned to provide a storyline for “The Space War” The Third Doctor
21 Recording for The Mind Of Evil takes place in BBC Television Centre Studio 3 The Mind Of Evil
22 Recording for The Mind Of Evil takes place in BBC Television Centre Studio 3 The Mind Of Evil

December
4 Recording for The Mind Of Evil takes place in BBC Television Centre Studio 6 The Mind Of Evil
5 Recording for The Mind Of Evil takes place in BBC Television Centre Studio 6 The Mind Of Evil
11 Recording for The Mind Of Evil takes place in BBC Television Centre Studio 3 The Mind Of Evil
12 Recording for The Mind Of Evil takes place in BBC Television Centre Studio 3 The Mind Of Evil
17 Robert Sloman is commissioned to provide a storyline for The Daemons The Daemons