Elementary 10 p.m., Channel 4

This is a relatively painless hour. And it’s easier to watch knowing that the showrunner, Rob Doherty, has made a public promise that Sherlock (Jonny Lee Miller) and Watson (Lucy Liu, above with Miller) will never, I repeat, never be romantically involved. It’s not nearly the show that PBS’s “Sherlock” is, but it’s a pleasant enough New York procedural, especially if you can block out Arthur Conan Doyle. Tonight, the pair try to find a missing child.