With Doctor Who’s 50th anniversary around the corner, 1973’s The Three Doctors is an object lesson to today’s fans about the sensible limitation of one’s expectations.

All the auspices are great. A Radio Times front cover. A threat to the Doctor so great, it necessitates the intervention of the Time Lords. And yet, there’s no getting away from it: the ‘interest’ in the opening fifteen minutes comes from… controlled super-lucent emissions. Well, quite. Whichever way you look at it: it’s still death by special effect.

Still, it’s the First Rule of Who that no story with Patrick Troughton in it can be anything less than entertaining, and, as soon as he appears, the story becomes a rather jolly romp.

As Doctor Who writers, Bob Baker and Dave Martin are unlikely to be at the top of anyone’s ‘most favourite’ lists, and yet the weaknesses in their stories are often as much to do with production values as they are plotting. Here, the worst offenders are Omega’s Aladdin’s Palace realm and the Gel Guards: glittery acne explosions that womble along with all of the menace of giant jelly beans.

Not everyone is served well by the script. Ditsy, Beatles-loving Jo Grant veers between the surprisingly perspicacious, surmising that the energy emissions are targeting the Doctor, and the frankly bonkers, believing a Rickmansworth quarry to be heaven.

But when the squabbling Troughton and Pertwee are interrupted by the hectoring admonitions of William Hartnell, there’s undeniable magic in the air – as well as lines so quotable, you can believe that one half of the writing team went on to pen Wallace and Gromit.

Extras: A double-disc package of bonus features combines new material with extras familiar from the original release of The Three Doctors in 2003.

Of the new material, Happy Birthday to Who is an account of the making of the story, with contributions from Terrance Dicks, Katy Manning, Bob Baker and, in archive footage, the always urbane Barry Letts.

Was Doctor Who Rubbish? asks a rather earnest documentary that seeks to tackle all the usual criticisms of the classic show – bubble-wrap monsters; rubbish acting; shot in a quarry – but doesn’t really have that much new to say on the subject.

A number of articulate fans line up to tell us that, yes, the Trial of a Timelord spaceship is really rather cool. But it’s only professional writer, Joe Lidster, who takes the discussion forward with a robust defence of the programme’s ability to inspire the imagination.

Girls, Girls, Girls: The 70s sees three of the Doctor’s former companions – Caroline John, Katy Manning and Louise Jameson – unite to discuss the perils and pitfalls of being a Who girl. There’s a certain camp appeal to the three of them meeting up again. It’s not every conversation between three seasoned actresses that features the query, ‘Were you from an alien planet?’ Nor is it every day you’ll hear Liz Shaw compliment Leela on ’looking really lush’ in leather.

Much of their conversation covers old ground: Jameson repeats her arguments from the Robots commentary that Leela rode ‘the crest of the feminist wave’, but had to take her clothes off to do so. But an interesting discussion on the subject of sexism leads to a Countdown of a conundrum for the three actresses: what would you most desire – the lover of a lifetime or the best TV series ever? Cue anxious ripostes from Who fans keen to respond that Doctor Who is the best TV series ever.

There’s no new commentary this time round; but the old one, featuring Katy Manning, Nicholas Courtney and Barry Letts still stands up as good fun, and acquires a new poignancy following the losses of the latter two commentators. If it thrills you to hear that Omega was originally named OHM, because it is WHO upside down, then it’s fair to say that Y.A.N.A.

Also included from the original DVD release is a lengthy segment from Pebble Mill at One, featuring Patrick Troughton being rather evasive and capricious with an interviewer obviously going through the motions, and the young son of singer Paul Jones proving very knowledgeable on the subject of Gel Guards and invisible Spirodonians.

When said invisible aliens wobble on, disguised as the love children of a shag pile carpet and one of Katy Manning’s groovy King’s Road coats, it’s suddenly clear why Pebble Mill’s presenters are treating the segment with a mixture of bemusement and condescension.

Released on DVD on Monday 13th February 2012 by 2entertain.

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