'Taggart' had declined quite a bit by this point. There was a feel of it having run out of ideas and had completely lost its spark. Especially in the later Burke period episodes, that suffered further from the shorter lengths. "Pinnacle" was one of the Burke period episodes that somehow was seen later on after the show had ended, shortly before getting into the Taggart and Jardine eras (and much preferring them on the whole in all honesty).
"Pinnacle" is also one of the not many great episodes of late-'Taggart' during the period when Burke was in charge. After a fairly long string of disappointments, where it seemed to indicate that it had completely lost it, it was great to see the show on brief form with "Pinnacle". It is easily the best episode since "A Death Foreold", which feels like a long time ago, and proof that 'Taggart' had not completely lost its spark when it declined and that it was still just about worth sticking with.
My only complaint actually is the now rather out of date and not very well fitting music. It was fine in the 80s and 90s and fitted then, at this point it was at odds with the action and like 10 plus years too late.
Other than that, "Pinnacle" has a huge amount to like and even love. The photography is both gritty yet moody, very well suited to the story's style, and the location is striking yet suitably unforgiving. The theme tune is hard to forget and still works, it's the background music that doesn't work and there has been nothing held against the theme tune.
From a writing point of view, "Pinnacle" has the right amount of entertainment value (the banter) and grit (in the crime solving it doesn't shy away). The story is never too simple, the murderer and motive this time were a shock and not prematurely foreseeable this time, or hard to follow. The team interaction hasn't lost its cohesion or grit. The episode is well paced too, taking its time to breathe while still having momentum, and there is grit and tension throughout.
Blythe Duff always delivered as Jackie and she gives another one of her best performances here, surpassed perhaps only by "A Death Foretold". John Michie also engages a good deal and have always dug Robbie and Jackie's chemistry. All the acting is fine.
In conclusion, great. 9/10.