Here in the UK we got the ATV In Colour titles as seen above. What memories those titles bring back for me - one of these days I am going to get round to writing the post I keep talking about, about UK regional TV stations, not least because it will force me to get the matter finally clear in my own head. Then after the ATV thing we're straight in to Ian Hendry's hairy chest without a pause. I love the way he sucks his gut in while talking to the doctor about how his clothes would fit him!
This episode is what it is. It would be wrong to expect too much of it, since the (spoiler alert) twin device is a plot device which is genuinely ancient. This episode attracts valid criticism that it is always easy for the audience to tell which twin is which. They could have had the good twin in league with the bad twin, or had the bad one murder the good one, or whatever. The real problem is that once you know there are twins it becomes obvious how this will end.
Stellar performance, though.
I am slightly disappointed to find that the box set doesn't include some cut scenes, which are nonetheless available on t'internet: