Have loved 'Taggart' (another show gotten into during my teenage years) for a long time, although the more deliberate and even grittier Taggart and Jardine periods to me are superior to Burke's. Although it was actually through watching the late afternoon reruns of the Burke period episodes (starting from "Compensation" right up to when the episodes became shorter, too short in my mind) at one point that got me hooked, the Taggart and Jardine episodes were actually seen a lot later.
"Crossing the Line" was one of the first Burke period episodes seen (saw the show out of sequence when first getting into it). Liked it but not loved it on first watch, and my feelings are pretty similar now since watching it when it first aired. Have always found a lot to like about "Crossing the Line", such as its atmosphere, but it does have a few of the flaws that most of the later Burke period episodes had when the episodes became shorter (which to me was a misjudgement).
Quite a lot is good about "Crossing the Line". It is typically slick-looking and it is good that the photography doesn't try to do too much stylistically, without being too clean looking. The grit has definitely not gone. The theme song is still memorable and has an appealing nostalgic vibe, as well as well suited to the tone of the show. The acting from all is good, with all four regulars faring strongly (particularly Blythe Duff) and the supporting cast doing nicely despite being in quite standard roles.
Complete with a nice chemistry that is humorous in parts and intense in others. The episode starts off very promisingly as said and the episode is disturbing in many places. One of the murders, the one around the halfway mark (or close to it), in fact is one of the latter seasons' most brutal and had me squirming on first watch. Which is not a bad thing, brutal 'Taggart' murders always make me wince and squirm and it never feels gratuitous.
There were things though that could have been done a lot better. The music still doesn't really fit, feeling 10 plus years out of date (perfect in the 80s and early 90s episodes but very dated in the later Burke period episodes). The episode also suffers from the same two things that spoilt the show when episode lengths were shortened, with it being yet another episode to feel too short and too rushed. Especially towards the end.
Surprises are too few, was not surprised by the solution, actually guessed the identity of the killer two thirds of the way in and the motive is obvious very early on.
In summary, decent but not great. 6/10.