Although they’ve barely had time to become acquainted, already the enmity between Kessler and Brandt is simmering away nicely. On observing Kessler’s departure to personally locate evading British airmen, Brandt is mildly amused. “Isn’t there a saying about having a dog and barking oneself?”

Kessler icily counters that he bites rather than barks and follows this up by stating that “I suspect there is one fundamental difference between us. My work matters to me”. Not the beginning of a beautiful friendship then, but the conflict between them (sometimes open, sometimes concealed) will provide the motor which drives many episodes during Secret Army‘s first two series.

There’s a lot to enjoy in John Brason’s Sergeant on the Run, even if certain parts (which I’ll get to in a minute) are rather baffling. Positives first. There’s a noticeable shift in tone from the series’ opening episode in terms of how the escaping airman are portrayed. In Willis Hall’s script everyone seemed to treat it as a bit of lark, but that’s certainly not the case here.

A fair amount of this episode was shot on film. Director Viktors Ritelis certainly makes his mark during a lengthy film sequence set in a café. Three extremely nervous British airmen are waiting to be collected – all they have to do is act naturally, but even that seems beyond them.

You could argue that Ritelis’ work is a little showy and obvious (a close up on a fly trapped in some flypaper mirroring the desperation of the airmen as they see enemies all around them) but all these visual touches manage to create a sense of tension and unease which – due to the length of the scene – becomes almost unbearable.

When eventually the airmen are spotted by some German soldiers, two make a break for it and are shot dead. The third, Sergeant Walker (Martin Burrows), hides and eventually slips away.

My first query is why the Germans didn’t seem to realise that there were three suspects not two. There were three meals on the table, so why not hunt for the missing third man? Maybe they were just happy with shooting two ….

Given the episode title, we’re now set up to assume that Walker’s evasion from capture will be the focus of the story from now on. Well, not really. After some more disorientating film work he’s rather easily picked up and delivered into Kessler’s hands.

Burrows excels at teasing out Walker’s character – he’s no laconic hero, rather he’s a bewildered and frightened young man desperately searching for a way out.  When he spies that there’s no guard on the door (yes, really – Kessler’s security leaves a lot to be desired) he makes a break for it. Having only got a few hundred yards he chucks himself over the stairwell, plummeting down multiple floors, rather than face recapture.

This is another well executed film sequence – not only Walker’s fall (which looks pretty convincing) but also its sequel, where an incensed Kessler attempts to question the bloody and broken Sergeant while an appalled Brandt looks on. Their brief battle of wills – won by Brandt who orders an ambulance – is another of those moments that’s a gift for both Culver and Rose.

Another plot oddity is that our first glance at Walker in hospital shows him to be in a pretty bad way – a bandaged leg in traction, arm in a sling, neckbrace – and yet shortly afterwards he’s lost all of these things and looks pretty much like his old self. And then a scene or two later he’s beginning to walk with crutches and gets on with them so well that he’s able to hotfoot it away from the doctor (Brandt’s guards – like Kessler’s – seem woefully inadequate).

Whilst all this is going on, the Candide regulars are beginning to enjoy some more character development. Albert and Monique share a nice relaxed scene in which Albert wistfully recalls the first time they met (this brief moment of peace is rudely interrupted by the angry knocking of Albert’s bed-ridden wife). We don’t actually see her in this episode, but then we don’t need to – just the banging and Monique’s anguish at being the mistress of a man still guiltily devoted to his wife tells us all we need to know.

The end of the episode feels like it could have done with a redraft, but since John Brason was also the series’ script editor he had no-one to blame but himself. Walker, having endured a nightmarish travelogue, hasn’t found anyone to help him (his inability to speak the language being a bit of a problem). Having collapsed on the street in despair, he’s immediately collected by two ambulance men.

In the next and final scene Albert tells the others that Walker is dead – shot with a German bullet. Since we’ve already seen Albert preparing a gun, the inference is clear (Walker, a weak man who knows far too much about the escape line, has been silenced for the good of Lifeline). 

What’s slightly jarring is the fact that Albert didn’t seem to be present when Walker was picked up, not to mention that if they’d got him to the ambulance, surely they then could have taken him to a safe house (no German soldiers seemed to be in the area).

Albert as killer is a powerful way to end the episode, demonstrating even this early on that he’s quite prepared to do any dirty work that’s required (it won’t be the last time either). It’s just a pity that the moment seems slightly bungled – and this, not to mention the way the Germans lose Walker twice, slightly drags the episode down.

A pity, because otherwise it’s a taut tale thanks to Martin Burrows’ turn as Walker. Surprising that his film and television credits were so slight (seven other roles between 1977 and 1982) as he more than holds his own here.