"Under the Bridge" (Red Hot Chili Peppers)

“Under the Bridge” from Blood Sugar Sex Magik (1991) remains one of my favorite Red Hot Chili Peppers tracks.  From the moment I heard it on MTV years ago, I immediately loved John Frusciante's delicate but funky playing.  It ripples like water over Flea's melodic and tasteful bass groove.  It always reminded me of a Curtis Mayfield tune in the way its complex, jazzy melody unfolds; Anthony Kiedis's confessional lyrics about junkie life in inner city L.A. also make it feel a bit like a lost track from Super Fly.
For as many times as I've listened to the song, the sudden key change at the climax—when Chad Smith's drums kick in and the band shifts gears for the dramatic conclusion, never fails to sneak up on me.  It's an unexpected move to go from a major to a minor key at the end of a song; the natural tendency is to ascend as you reach the denouement.  But that's what pulls at the ear and creates intrigue.  It's also quite simply an intelligent bit of musical composition that underscores the shift in emotion from bittersweet melancholy to outright regret in Kiedis's lyrics.  (That final 1:30 signaled to me there was more going on in the hearts and heads of these guys than just "Yertle the Turtle.")
In his 2004 autobiography Scar Tissue, Kiedis discusses the composition of the song.  He recounts that he'd kicked his years-long addiction to heroin and was dedicated to staying away from any kind of drugs, which caused an unintentional rift between him and Frusciante, who (along with Flea) was a proponent of smoking weed as part of the writing/recording process.  Kiedis says he felt shut out by his bandmates, which brought up old emotions about his painful breakup with actress Ione Skye—the result of his drug use spiraling out of control.
Channeling his emotions, he wrote a poem in his notebook that simultaneously addressed his feelings of regret for letting drugs ruin his relationship and expressed gratitude to the spirit of L.A. for watching over him like a guardian in his darkest times.

"I felt I had thrown away so much in my life, but I also felt an unspoken bond between me and my city.  I'd spent so much time wandering the streets of L.A. and hiking through the Hollywood Hills that I sensed there was a nonhuman entity, maybe the spirit of the hills and the city, who had me in her sights and was looking after me.  Even if I was a loner in my own band, at least I still felt the presence of the city I lived in."

Kiedis never intended for the poem to be song lyrics, feeling that the tone was much too soft and somber for the band.  It ultimately took producer Rick Rubin stumbling upon the poem in Kiedis's notebook and urging him to take it to his bandmates to spark the composition of one of the most honest, cathartic songs of the 1990s.