Marineville Traitor is an unusual episode of Stingray in that it is the only installment of the series in which the eponymous vehicle doesn’t appear. This is all the more unusual as the series’ predecessors had deliberately introduced all manner of futuristic vehicles just to avoid having the puppets walking, and it wouldn’t be until Joe 90 that the emphasis on talk would outweigh the effects.

The Hydroprobe, a new piece of equipment, is stolen from the Control Tower during the night. The next day, Commander Shore is caught sending a suspicious message to an unknown contact which implies Atlanta may be in danger - the Commander insists unconvincingly that it was meant as a gag. The next night, Shore is apparently attacked while alone in the Control Tower, and secret plans are stolen form the safe. Suspicious of Shore’s feeble ‘gag’, Troy investigates; when he catches Shore transmitting again, he has no alternative but to place him under arrest. While in the cells, Shore is contacted by Lieutenant Mizen from the Tracking Station, who has been monitoring all messages in and out of Marineville. Mizen reveals it was he who stole the Hydroprobe. Assuming that Shore has the stolen plans and is also working for ‘our underwater friends’, Mizen plans that they should fight their way out of the jail. Shore reveals his actions were all part of a plan to expose a suspected traitor in Marineville, a scheme which had to deceive even Atlanta to work convincingly. Troy arrives to save the day and it’s Mizen who ends up behind bars.

Alan Fennell, the episode’s writer, had joined the Andersons on Fireball XL5 after impressing them with his scripts for the Supercar strip in TV Comic. Fennell was not only a prolific writer but also one capable of writing episodes that worked on several levels, to engage the attention of the older viewers as well as the youngsters. It was to the series’ lasting benefit that Fennell and Dennis Spooner wrote virtually all of the episodes between them, and it was their good fortune that they had such a rounded bunch of characters to employ.

The episode uses restricted narration to plant a number of false or ambiguous clues which when put together, point to a familiar character apparently working for the other side. At no point in the story does the viewer know more than Troy or Atlanta. It’s only at the end do we realize that we were only given some of the facts, leading us (and the other characters) to an incorrect conclusion. Pretty much everything seen on-screen is part of the cause-effect logic of the plot. Narrative theorist Tzvetan Todorov (hands up who’s been reading a book on film studies!) structures the narrative in three stages - the beginning (the initial state of equilibrium - Shore as Commander), the middle (disruption of the equilibrium - Shore suspected of traitorous activities) and the end (restoration of equilibrium - Shore found to be innocent). However the transformation in this narrative is not Shore’s but Mizen’s, who is exposed as being the traitor and loses his freedom.

The plot is reminiscent of many of those American sci-fi flicks of the 50s (fresher in the minds of the writers back then than they are now) which featured as their subtext the fear of Communist invasion assisted by homegrown sympathizers. Here it is Lieutenant Mizen who is the contact, doing the bad guys’ work amongst us. This Cold War paranoia along with the demonizing of the ‘enemy’ by official sources was a fertile source of inspiration for many episodes of the Andersons’ early series - it’s a theme that runs through the heart of Stingray with its underground bunkers, lurking spies, unprovoked attacks and immediate missile responses. That’s the good old days of the early 60s for you, in case you were feeling nostalgic.

The advent of colour filming had brought a technicolour (or should that be videcolor) approach to design. Despite being a military base, Marineville is decked out in some bright pastel tones; restraint and subtlety go out of the window as every alternate wall and console is painted a different colour. It’s no surprise that Stingray was the first British series to be filmed in colour - it’s probably the most colour series ever! This unrestrained approach to colour gives the series a more cartoony look, a fantasy edge that suits the caricatured figures, something which later Anderson series would gradually move away from.

The episode itself is built around the characters and is not dependent on effects sequences which don’t motivate the plot. Troy, Atlanta (and the viewer) know Commander Shore and initially can’t accept that he could have changed allegiances. However Troy investigates further and only when confronted with proof does he intervene. Atlanta is unaware of Shore’s covert plan; she doesn’t want to accept the evidence and pleads with Troy to help her father. Both characters keep their faith in Shore and this is what eventually leads Troy to unmask the real villain. This being the 60s, the female characters don’t get too much to do; Atlanta remains peripheral to the plot while Marina just goes AWOL. It would have been nice if Atlanta had at least assisted Troy in uncovering the truth about her father rather than just asking for his help.

Stingray, of all the Andersons’ series, is squarely aimed at an American audience. The cast and locations are all American - no Scottish engineers or London agents - and the dialogue is tailored for a Stateside ear, all considered essential to guarantee an American sale. So we get the likes of ‘I don’t figure this’, ‘I could use the time’ and ‘Guess we’re both on the same side’ - terms of speech hardly in common usage by us Limeys back in the mid-60s. As a youngster, it never occurred to me that Stingray was anything other than an American-made series; it was ironic to learn it was actually produced in the shadow of the Mars Bar factory in Slough. In other words, guess I didn’t figure that at all.

An episode of Stingray without Stingray sounds like a contravention of the Trades Description Act and goes against the grain of the adrenaline-charged opening credits and the other 38 episodes in the series. However, like Fennell’s Invisible Enemy, the story works because the characters are rounded enough for us to identify with. It's also well-paced and suspenseful, keeping the viewer guessing until the end. It wouldn’t be until Joe 90 that such a thing would be tried again, albeit with less success. Like the aforementioned Invisible Enemy, Marineville Traitor treads a less familiar path and adds unexpected depth to one of the Andersons’ finest series.