"Certainly It Was Impossible — Except That Mr. Gru Was Stone Cold Dead . . ."

WOULD YOU BELIEVE a story set a couple of centuries from now that's also a locked room mystery? Uber-editor John W. Campbell would probably scoff, but, as our sleuth says, "You were wrong about nothing having changed in the past two hundred years. This was a crime which could not have happened then."

"The Closed Door."
By Kendall [sic] Foster Crossen (1910-81).
First appearance: Amazing Stories, August-September 1953.
Reprinted in Amazing Stories (U.K.), December 1953 and Fantastic, February 1969.
Short story (18 pages).
Online at SFFAudio (HERE) (PDF) and Archive.org starting (HERE) and finishing (HERE).

"This is a detective story. Without, we hasten to add, private eyes, blondes, beds, bigamy or bottles of bourbon. The setting is a luxurious interplanetary hotel three hundred years in the future . . ."

They say when one door closes, another opens; in the matter of the murder of the humanoid from Sirius II, it ain't necessarily so . . .

The whos in this whodunit:
~ G. G. Gru:
  "If there's one thing I can't abide, it's practical jokers."
~ Alister Chu, manager of the Planetary Rest Hotel:
  ". . . quickly told of the call he'd received from the guest on this floor. He explained
the whole thing in great detail, including his impression of the guest's falling apart:
'Not literally, of course.'"
~ Chief Inspector Maiset, head of the Solar Department, Terran Division, Interplanetary Criminal Police Commission:
  "It's suspected murder and delicate interplanetary relations."
~ Detective Inspector Jair Calder:
  "If Gideon Fell could have lived to see this . . ."
~ Sub-Inspector Aly Mordette, Provincial Police:
  "Oh, we have our Twenty-second Century gadgets, but everything works just the same
as it did in the Nineteenth or Twentieth Century. You can take my word for it, Inspector."
~ James Bruce, an employee of Plasticorp and chairman of the Acrylic convention:
  "'I do hope, however, that your investigation won't disturb our convention too much.
We have some pretty important men here.' He bore down on the word important just
enough."
~ Cooerl II, a Mercurian:
  ". . . I went to the public visiphone booth at the end of the corridor. But there was no
one there when I answered. Apparently the party had hung up, or it was a practical joke."

Resources:
- Some of Kendell Foster Crossen's writing seems to have been influenced by his experiences as an insurance investigator; see Wikipedia (HERE), the SFE (HERE),
and ISFDb (HERE) for the 411 on him.

- Sundry heavenly bodies get a brief mention in the story: Acrux (HERE), Canopus
(HERE and HERE), Mercury (HERE and HERE), Algenib (HERE), Sirius (HERE
and HERE), Mars (HERE and HERE), Rigel (HERE and HERE), Aldebaran (HERE
and HERE), and Antares (HERE and HERE).

- Silicon-based life forms have been popular in SFF for a long time; see David Darling's Encyclopedia (HERE), Wikipedia (HERE), and Scientific American (HERE).

- Another story blending SFF and tec fic is Fredric Brown's "Daymare" (HERE).

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