A couple of times on the podcast the short story that was the inspiration for The Day the Earth Stood Still
was mentioned. Farewell to the Master by Harry Bates was originally published in 1940 appearing in the magazine he co-founded Astounding Stories of Science-Fiction
I sought out this story and was happy to find that it is now a public domain item. I found it at a website, manybooks.net
This is a short read, only 44 pages, and for any fan of the 1951 film I think a must read to see where the origins of that story came from.
The books plot is very different than the film but it is easy to see all the elements that eventually created the sci-fi classic. Klaatu is, not to give any spoilers, less than even a minor character in the story, instead focusing more on the robot, here named 'Gnut' and a reporter assigned to the continuing coverage of the 'alien' visitors.
The short story reads like an idea that in the end was not fully formed and the twist ending feels a bit forced. Being written in 1940 the cold-war, anti-atomic message was obviously absent and instead a simple investigation of a mystery was in place.
To be honest, I mush prefer the events of The Day the Earth Stood Still
and the ideas it was trying to convey but I really don't think it would be fair to try and compare the two in that way, but rather just look at this story as its own entity and the inspiration for the film and nothing more.
A read I'd recommend and at that link above you can download a copy of the story in a variety of formats, E-readers, text, PDF, etc.