Steve Schwartz:

>>Marius Constant.  The theme was, I think, for Twilight Zone (or was that
>>Bernie Herrmann?).

Roger Hecht:

>Twilight Zone was Herrmann, I'm pretty sure.

Here's the actual story, from
http://www.classicthemes.com/50sTVThemes/themePages/twilightZone.html:

   In 1960, CBS Music Director Lud Gluskin was asked to find a
   new Main Title/End Credits THEME for the second season of the
   series, to replace the original THEME written by veteran
   radio/TV/film composer Bernard Herrmann. The problem was
   thought to be that the Herrmann theme was considered "too
   down" according to music supervisor Don B. Ray, quoted in the
   book "TV's Biggest Hits" by Jon Burlingame. However new visuals
   had been created, with some bizzare [sic] items floating
   around in the style of a Salvador Dali abstract painting, so
   that required a new scoring approach...if for no other reason;

   So several new THEMEs were commissioned and recorded for CBS
   including two new THEMEs submitted by Bernard Herrmann, one
   by Jerry Goldsmith, another by Leith Stevens, and a few other
   composers familiar to CBS; but none of these was deemed
   suitable...(they were eventually incorporated into the CBS
   Cue Library and used to score episodes of "Twilight Zone" and
   other shows...)

   Finally in desperation, Lud Gluskin tried splicing together
   two short cues written by a French Avant-Garde classical
   composer Marius Constant -- who had composed them for CBS to
   use as backgrounds for episodes of "The Twilight Zone", and
   then recycled in the network cue library. CBS had a policy
   in those days to have music composed and recorded overseas
   to skirt US Musician Union re-use fees which were 100% of the
   original session fee for any subsequent re-use. This policy
   was intended to keep producers from using recordings over and
   over, but it had the opposite effect -- inspiring producers
   and networks to find alternatives and music packagers who
   recorded outside the U.S. so they could use "track" (re-cycle)
   cues...

   Such commissioned cues were available to be shared by any CBS
   series which needed them. The internal title for this cue
   library was the "CBS Foreign Library".

   The cues which Gluskin spliced together were originally named
   "Etrange 3 (Strange No. 3)" and "Milieu 2 (Middle No. 2)".
   They were so fragmentary and unusual that they had not been
   used much.  These were two of the six short dramatic cues
   Constant wrote and recorded with a small ensemble featuring
   a two guitars, percussion including bongo drums, a saxophone
   and French horns.

   They had never been designed to be a Main Title or End Credits
   THEME. Spliced together by Gluskin, their unique qualities
   appealed to Serling, who was looking for something different.
   So TV history was changed when they became the new "Twilight
   Zone" THEME from the 2nd season on...and now the most recognized
   by the atonal guitar motif which opens "Etrange 3."

   In 1982 correspondence with composer Constant, he explained
   that in 1959 he composed six cues at the request of Lud Gluskin
   "for a few hundred dollars"; He knew they were intended for
   their first use on a new show described by CBS as "strange,
   incredible, bizarre, fantastic"; Composer Constant went on
   to say it  wasn't until much later that he learned that two
   of his cues had been spliced together to become its Main Title
   and End Credits THEME for this U.S. Television series;

   Hopefully his ASCAP performance royalties as well as any
   mechanical royalties from future recordings helped soothe his
   astonishment.

- seb