I didn't really like it. It's watchable and it's got Sid James in it, but Dave Freeman seems to think that writing a Carry On storyline means it's okay to churn out any old tripe.
As the name suggests, it's a parody of The Prisoner of Zenda. It's not the first, of course. Significant movie adaptations include the 1937 one with Douglas Fairbanks Jr, a shot-for-shot 1952 remake with Deborah Kerr and James Mason, a subplot in The Great Race (1965) and a 1979 comedy with Peter Sellers and Elke Sommer. As for TV, I couldn't not mention The Androids of Tara, but there's also Get Smart and a well-regarded episode of Futurama as well as more mainstream adaptations like the 1961 American one and the BBC's 1984 series. There's also a 1996 TV version set in modern America with William Shatner in it.
Anyway, this is a terrible adaptation. Theoretically it should be harking back to the good old days to see such a specific Carry On parody, because they did lots of them in the 1960s... Cleo
etc. Unfortunately Freeman is taking a rather impressionistic approach to his parody. He steals the basic idea, then uses it as a loose framework for silly scenes that aren't even pretending to hang together. These include:
(a) the notion that if you give a sword to a short-sighted man who's not wearing his spectacles, he'll go on a rampage of destruction that continues beyond all credibility until he gets his glasses back on. This isn't because he's afraid or trying to defend himself, by the way. He hasn't realised he's doing anything odd.
(b) when your murderous mortal enemy (David Lodge) is unconscious before you, the correct thing to do is walk away.
(c) David Lodge has previously saved Sid James from drinking a poisoned drink, despite the fact that he'll soon be trying to kill him and furthermore no one had any reason to administer that poison except Lodge himself.
(d) being poisoned is a temporary condition anyway.
By the time we reach the finale, with sword fighting and two Sids, I'd stopped caring. If even the scriptwriter thinks his own plot is bollocks, who am I to disagree? The duplication of Sid James is well executed, mind you. They make the split screen look natural rather than a special effect.
That said, I liked the cast. Sid James only appeared in the first four episodes of this show, but furthermore due to the nature of the plot here he's creating two different personas instead of just playing a crooked old lecher again. Prince Sid has an East European accent (!) and an air of command. He seems like both a king and a tough guy. British Sid on the other hand is travelling on honeymoon with Barbara Windsor, is almost blind without his spectacles and might be a vicar. I'm probably wrong on the last of those, but that white collar of his does look awfully like a dog collar. Anyway, British Sid is a gentle old soul with no interest in philandering and... yes, you can pick yourself up off the floor now. He's quite sweet, actually. I've always loved Sid James, but he's also fully capable of stepping outside his usual Carry On stereotype and I always relish it when he does.
Barbara Windsor is occasionally a tad annoying as his new bride, but she gets the episode's best laughs. Unintentional innuendo is twice as funny when delivered to a childish newlywed.
Of the others, Joan Sims is as game as ever, but I have no idea what her accent's meant to be. Jack Douglas is almost unrecognisable as the priest-like Colonel Yackoff. Kenneth Connor and Peter Butterworth show up too. With all these familiar faces, it feels like a Carry On despite the drop to TV production values.
Fundamentally nonsense. It's nice to see everyone together and they're making a decent fist of the available material, but it would have been even nicer to watch them in something good. Not only does this lack internal coherence, but it thinks that's okay because it's a comedy. There's cleavage, but even that manages to be oddly unappealing. Maybe this episode would work better if you regarded it as a sort of sketch show around a The Prisoner of Zenda theme? It's okay, I suppose. I've seen worse. It can be amusing and it has a certain amount of energy, but there's no way you'll catch me recommending this one.