A two-part TV adaptation of Agatha Christie's The Pale Horse is scheduled to air on BBC One in the U.K. and Amazon Prime in the U.S., and it seems people are a bit miffed... even though it hasn't aired yet.

Sarah Phelps (Dublin Murders), who already adapted Christie’s Ordeal by Innocence and The ABC Murders for TV, will be handing writing duties. In case you missed it, here's a look at the trailer with Rufus Sewell taking the lead as Mark Easterbrook, a man living a charmed life… up until his name turns up on a list in a dead woman's shoe, that is. 

It appears Phelps is leaning heavily on artistic license and viewers are noticing. But rather than shying away from criticism, the writer addressed the concerns, saying, "The whole point is that somebody as famous as Agatha Christie, as widely read, as globally read, who has been read for all this time, you kind of lose sight of the fact that there’s a brain writing behind this. You can get swallowed up by your brand," according to Radio Times. 

If that doesn't quite squash it for naysayers,  she went on: "Yes, of course I’ve taken liberties. Have I changed a load of stuff? Yeah, of course I have, loads and loads and loads of stuff. Otherwise you’d have 30 hours of TV and would you want to watch it? No."

That's not to say she went completely rogue. "But, you always go for the beating heart of what she’s getting at," Phelps continued. "She always throws you little clues, little quantum details and those are the things that I latch onto because that’s what I think the story is about from her point of view.”

If this is new to you, we noticed that one of the things she changed, is that in the book, the woman passed along the list of names to a priest, prior to dying. But, in the TV version, the list is found in the dead woman's shoe. Like Phelps says above, it seems like the changes are to help speed things up a bit and get to the point.

If you'd like to do a compare and contrast — or just enjoy the series for what it is — The Pale Horse will air on February 9 in the U.K. and March 13 in the U.S.

Are you okay with writers tweaking classics for the screen?