Is it copying to use the same concept as another writer?
There is a moral element to what could be looked at solely as a legal issue. Personally, I wouldn’t consciously copy another artist.
That said, writing teachers sometimes have students undertake the style of a great author as an exercise. I don’t understand why. For me, the whole point of writing is to find your own voice. For the market, a writer’s voice is the only of the few truly unique part of what a book has to offer.
Occasionally, you get a plot like Annie Proulx’s short story, “Brokeback Mountain” or my recent obsession, Percival Everett’s novel, James. By and large, most stories are variations of other stories.
Also, there is a whole genre called “fan fiction,” wherein the writer deliberately writes in the style of the writer they are mimicking. In general, it is considered an homage. However:
Legally:
In this great country of ours, anyone can sue anyone for anything—if you can find a lawyer to represent you. Should you use another writer’s concept, you might get dragged into a lawsuit and you might not.
The law is that the new piece has to change 30% of the original work. What 30% looks like in any project is up to the judge. And the readers!