I wish more television was like this. Jekyll is a six episode BBC mini-series that tells the story it wants to tell without a wasted episode, or arguably even a wasted scene. Writer Steven Moffat (becoming well known for the standout episode of Doctor Who every year) gives the Jekyll and Hyde story an update, leaving out potions in favour of Jekyll and Hyde using high-tech tracking devices on each other, themes of genetic tampering, greed, inheritance and corporate abuse, making it far more than just the story of a man and his darker side. Moffat has a tendency to telegraph what's about to happen in the next few seconds with a little too much set up, but the overall plot keeps the viewer guessing.
James Nesbitt is excellent as both Jekyll and Hyde, and the supporting cast are uniformly good as well. As for the production the score is good and the budget apparently a decent one, though there is a frustrating tendency to build up to action sequences that are over in a second. But the action isn't ultimately the point, here. And in every other way, Jekyll is television as its best: engaging, full of ideas and great lines, well acted and produced.