"In the Mood" is three minutes and 34 seconds long. The song was composed in the key of A major and is in 4/4 time.[2][3] It is the only song on the album written entirely by Geddy Lee (the music on all other songs is co-written by guitarist Alex Lifeson).
Lee said that this was the first song he wrote with Lifeson that they "kind of liked".[4]
Lifeson said It "was probably at least two years old, if not three, when we recorded the first album". He also said: "Ged came in and said, 'I've got a good idea for a song' and played it from beginning to end".[5]
The song was played on every tour since it's release (often in a medley, and usually near the end of the final encore) until the 1992 Roll the Bones Tour, after which it was permanently dropped. In live performances, the line "Hey, baby, it's a quarter to eight" was often altered to include a woman's name in place of the word "baby". The St. Louisclassic rock radio station KSHE used to play the song every Friday night at 7:45 ("a quarter to eight").[6]
"In the Mood" was released as a single, reaching No. 31 in Canada [7]Cash Box said that "the Led Zep sound alikes are in strong form with a more innovative ditty than their last disk" and praised the vocals and backing instrumentation.[8]
