Sherlock
Steven Moffat (Doctor Who, Coupling) and Mark Gatiss (The League of Gentlemen, Doctor Who) co-created a reboot of Sherlock Holmes set in the modern day.
Clever, funny, and smart, this reboot ran for four series, each consisting of three episodes which are much more like feature films than television episodes in length, production values, and ambition. Like the Conan Doyle stories, each episode is a standalone story—often a modern-day update of an original Sherlock Holmes short story. Recurring characters develop over time, and maybe it all gets a little too much like a soap opera by the final episode. But the overall result is the product of two great storytellers pushing each other to create fun and satisfying television.
For my tastes, the series hits its high-water mark in series two. It was a little too self-aware and too much of a cultural phenomenon by series four to say anything fundamentally new. But there are no bad episodes here. They just range from great to phenomenal.