Holmes enters the arena.

Time to pull back and look at the big picture surrounding the upcoming Sherlockalypse called “Elementary.” While it’s easy to pick at details of the upcoming CBS series, the true problem roaring at us like a runaway steam locomotive is this: American television kills what it loves. And it tends to severely maim that which it doesn’t love, as well.

And Sherlock Holmes has entered that arena. The lions are coming, and here's what they look like.

If “Elementary” is a fan favorite, but doesn’t get ratings, it dies an early death, leaving plot threads hanging and fans in mourning. And that is a happy ending in TV land.

If “Elementary” is a ratings success and a popular favorite, things go from bad to worse. Think of all the TV non-sitcom shows you’ve seen that held together for a long and happy run. Show-runners, the creative heart of a TV show, leave, and things fall apart. (Think “Moonlighting.”) A major actor or actress can leave the show, and we wind up seeing something like Holmes replacing Watson, two years in. If the lead actor gains enough power and becomes lazy and egotistical, his character might develop more and more personality traits of the actor himself. (And we get Sher-onny Lee Hol-ler.)

And then there’s the inevitable shark-jumping. If square one of “Elementary” involves giving Holmes a previously-unhead-of father and a sober companion, what will we see five years from now? His twin sister? A Holmesmobile? Sherlock’s secret powers of telepathy revealed?

The arena of American television is a little like a mutant-filled, post-apocalypse landscape, where anything can pop up . . . and just might. I’ve taken a little heat for being so pessimistic about American TV’s take on a British favorite, but this isn’t my first TV series rodeo. I’ve always admired the BBC’s ability to tell a story on television in whatever number of episodes it took, without running a good idea into the ground. And I’ve also see MacGyver go from MIT genius work to A-Team level silliness on the American network TV side of things.

And now our friend Sherlock Holmes has entered that arena. Forgive me if I’m gritting my teeth for a bit until he makes it out in one piece.