CBS Radio Mystery Theater (a.k.a. Radio Mystery Theater and Mystery Theater, sometimes abbreviated as CBSRMT) is a radio drama series created by Himan Brown that was broadcast on CBS Radio Network affiliates from 1974 to 1982, and later in the early 2000s was repeated by the NPR satellite feed. The format was similar to that of classic old time radio shows like The Mysterious Traveler and The Whistler, in that the episodes were introduced by host E. G. Marshall who provided pithy wisdom and commentary throughout. Unlike the hosts of those earlier programs, Marshall is fully mortal, merely someone whose heightened insight and erudition plunge the listener into the world of the macabre. As with Himan Brown's prior Inner Sanctum Mysteries, each episode of CBS Radio Mystery Theater opened and closed with the ominous sound of a creaking door. This sound effect is accompanied by Marshall's greeting, "Come in!… Welcome. I'm E. G. Marshall." At each show's conclusion, the door swings shut, and Marshall signs off with: "Until next time, pleasant… dreams?" This is followed by an extended variation of the show's theme music. CBSRMT was broadcast each weeknight, at first with a new program each night. Later in the run, three or four episodes were new originals each week, and the remainder repeats. There were 1,399 original episodes. The total number of broadcasts, including repeats, was 2,969. Each episode was allotted a full hour of airtime, but after commercials and newscasts, each episode typically ran for around 45 minutes. Hosts E. G. Marshall hosted the program from January 1974 until February 1, 1982, when actress Tammy Grimes took over for the remainder of the series' final season, maintaining the format. Himan Brown re-recorded E. G. Marshall's original host segments for NPR's broadcast of the show in the 2000s. Music The series' theme music features three descending notes from double basses, a stopped horn sting and timpani roll, then a low, eerie theme played by the bass clarinet. The opening and closing themes for CBSRMT are excerpted from the music from the score for Twilight Zone episode "Two", composed by Nathan Van Cleave. Series listeners will immediately recognize the "RMT Theme" beginning about 1:35 on the "Two" soundtrack selection from the Twilight Zone CD boxed set. Other background tracks from the Twilight Zone music library, to which CBS owned full rights, were featured repeatedly in episodes of CBSRMT. The theme