In 1979, Collins was going through a divorce from his first wife, Andrea Bertorelli. He went on hiatus from Genesis, and recorded Face Value, an album primarily composed of songs intended to be messages to his ex-wife. The most successful song on Face Value, and arguably of Collins' career, was "In The Air Tonight." The phrase "in the air" was inspired by the lingering tension that Collins felt affected not only him and his wife, but their children. Collins has stated that even he isn't sure exactly what the song is about, but that it concerns the bitter, angry side of a separation [source]. His lyrics (particularly in songs like "Sussudio") are typically written as he sings, and based on what sounds good. "In The Air Tonight" is no exception. Collins responded to a particularly contradictory line, "The first time, the last time//we ever met" by saying:
"I didn't go back to look at the thing and say- 'Now, does this make sense? Because someone's gonna ask me years later.' I just said, 'does that sound good?' [...] Because I'm not very good with words. I mean, although I'm writing lyrics, I'm not very good with words talking. So, I thought, when she hears this she'll know how I feel."
Bertorelli left Collins after having an affair with a painter and decorator, inspiring Phil Collins to perform the song on Top of the Pops with a can of paint and a paintbrush onstage.
The recording of the drums in "In The Air Tonight" is notable. The sound actually came as an accident. Collins was recording drums for "Intruder," a Peter Gabriel solo track, when the reverse talk-back feature (which allows the producers to speak to those in the recording studio) was activated. Engineer Hugh Padgham was so impressed by the sound that he and a friend rewired the sound board so that the reverse talk-back could be used more formally. Later versions of the soundboard were made so that the listen mic could be recorded more easily. To create the sound of "In The Air Tonight," they also used heavily compressed and gated ambient mics. This sound (referred to as "gated drum" or "gated reverb") has become a trademark of Collins' work. When "In The Air Tonight" was released as a single, Atlantic Records asked them to add more drums earlier in the song.
Collins offered "In The Air Tonight" to Genesis, but the other members of the band felt it was "too simple."
This song, in particular the lines "if you were drowning//I would not lend a hand," has developed an urban legend surrounding it, creating several different backstories, none of which are true (although they are all more interesting than the actual story relayed above). This is all despite the fact that Collins himself has described the "drowning" lines as being symbolic, which makes rational sense.
The first story is that Collins watched someone fail to save a drowning person, from a distance too great to help himself. This story sometimes goes so far as to say that Collins hired a private investigator to find the man, and then sang it to him for the first time at a concert with a spotlight on the man. Another story says that Collins watched a man who had raped his wife drown. A third story claims that Collins himself saw a man drowning when he was a child, but couldn't help. These stories are referenced in an Eminem song, "Stan."
"In The Air Tonight" has become an important part of pop culture, beginning as early as 1984, when it was featured in the pilot episode of Miami Vice. Possibly because of that inclusion, it is an important component in Grand Theft Auto: Vice City Stories.
It's been featured in a ton of movies and tv shows, including a scene in the series finale of Ashes to Ashes, in which the creator elected to fade the song down early, so the drum bridge didn't distract viewers from the drama of the show.
And that's all that I hath for now!