Inferno ★★★★★

Storyline
A project to penetrate the Earth's crust and release a new energy source starts to cause concern when its mastermind, Professor Eric Stahlman, rejects all safety warnings. Despite the Doctor's protestations about the terrible consequences for the planet, a green substance leaking from the drill head mutates those who touch it into heat-seeking, primordial creatures. An accident transports the Doctor and his Tardis console to a parallel world, where the Inferno project is closer to completion. Unable to prevent a catastrophe there, he is desperate to return to his own dimension and thwart a repetition…

First transmissions
Episode 1 - Saturday 9 May 1970
Episode 2 - Saturday 16 May 1970
Episode 3 - Saturday 23 May 1970
Episode 4 - Saturday 30 May 1970
Episode 5 - Saturday 6 June 1970
Episode 6 - Saturday 13 June 1970
Episode 7 - Saturday 20 June 1970

Production
Location filming: March/April 1970 at Berry Wiggins & Co Ltd, Hoo St Werburgh, Kent
Filming: April 1970 at Ealing Studios
Studio recording: April/May 1970 in TC3, May 1970 in TC6 and TC3

Cast
Doctor Who - Jon Pertwee
Brigadier/Brigade Leader Lethbridge Stewart - Nicholas Courtney
Liz Shaw/Section Leader Elizabeth Shaw - Caroline John
Sergeant Benton/Platoon Under Leader Benton - John Levene
Professor Eric Stahlman/Director Stahlman - Olaf Pooley
Sir Keith Gold - Christopher Benjamin
Greg Sutton - Derek Newark
Petra Williams/Dr Petra Williams - Sheila Dunn
Private Latimer - David Simeon
Private Wyatt - Derek Ware
Harry Slocum - Walter Randall
John Bromley - Ian Fairbairn
RSF Sentry - Roy Scammell
Patterson - Keith James
Primords - Dave Carter, Pat Gorman, Philip Ryan, Peter Thompson, Walter Henry

Crew
Writer - Don Houghton
Incidental music - library tracks
Special sounds - Brian Hodgson
Designer - Jeremy Davies
Script editor - Terrance Dicks
Producer - Barry Letts
Director - Douglas Camfield (and Barry Letts uncredited)

RT Review by Mark Braxton
If tone meetings had existed in 1970, the key word for Inferno would have been "intense". This exhausting seven-parter broke new ground with its relentless escalation of pressure, its ecological mindedness and dramatic dualism.

Such intensity seems to have spilled over onto the set - credited director Douglas Camfield suffered a minor heart attack and was replaced for episode three onwards by Barry Letts. The professionalism of the latter says much for his commitment to the show, both then and for years afterwards; here, he grasped the baton and ran with it to the bitter end.

Mankind's heedless plundering of the Earth is expressed in the story with haunting eloquence: "Listen to that," says the Doctor. "That's the sound of this planet screaming out its rage!" It's a theme we'll see again during Pertwee's Doctorial occupancy.

We're used to parallel-world stories in the modern era of Doctor Who, but in 1970 it was innovative, disorientating and shocking. The jackbooted, totalitarianism of "Sideways Earth" as visited by the Doctor is an officious, loveless world, full of Big Brotherly dogma - Nick Courtney, Carrie John and John Levene invest their mirror images with confounding malice.

Impending apocalypse and coexisting opposites would seem ample material to spin the tale out, but Don Houghton at some point injected monstrous diversion (the Primords were not part of his original concept). And Inferno certainly gives the horror button a vigorous twist, what with Stahlmann forcing a technician's head towards the gangrenous goop, the mad professor covering a screaming Benton's face with his hairy hand, and infected unfortunates plunging to their death from refinery gantry.

When I watched it as a child, the Primords seemed the best and most important part of the serial. The long-haired Max Wall-alikes were the inspiration for many games played by me and my best friend. Alas, my adult self sees them as a risible superfluity. The Quatermass-style transformations are fine, but the final effect - all Christmas-cracker plastic teeth and gurns into Camera One - leaves a lot to be desired.

In any case the relationship of the creatures to the waste product is never cleared up. It looks at one point as if the plotlines will be reconciled when the Doctor says he's heard a noise like their synthesized grunting once before - on Krakatoa. But it's a narrative cul-de-sac.

The main thrust of the plot, however, is good, scary, cautionary stuff, and the Doctor's salvaging of the situation (with the countdown clock stopped on 00:35, you'll notice - not the more clichéd 00:01) doesn't quite make up for the fact that we've seen the Earth die screaming.

Although he's the hero of the hour once again, the Third Doctor's jarring propensity for gentlemanly understatement continues. "You, sir, are a nitwit," he tells the patently insane Stahlman. He will go on to describe Hitler as a bounder in a later adventure.

Amid all the loss of temper and shouting-till-hoarse, there's solid work from Olaf Pooley as the intractable professor, Derek Newark as sexist troubleshooter Sutton and Chris Benjamin as the eminently reasonable Sir Keith. And two small but lovely moments make this a memorable final story for Caroline John.

The first is an eloquent silence from her Rosa Klebbish version of Liz. She disbelieves the Doctor's parallel-world theory until he asks: "Did you ever think of becoming a scientist?" Her confusion, in close-up, is the tiny breakthrough that makes a final redemption possible. The second is the corny comedy ending in which the Doctor dematerialises in high dudgeon into a dungheap, occasioning a lovely, naturalistic laugh from Liz. Hard to get right, laughter, but she nails it.