Steven Page has said that the song was partly inspired by "Back to the Old House" by The Smiths. While some have misinterpreted the lyrics to mean that the man in the song is stalking an ex-girlfriend and breaks into her apartment to terrorize her, Page has said that this is definitely not the case. The person in the song and his girlfriend are still together and happy, having "bought an old house on the Danforth" (Danforth Avenue in Toronto). However, he goes back to visit "the old apartment" "where we used to live," and winds up breaking in to reminisce. Although recalling "broken glass," the "crooked landing, crooked landlord," and other disadvantages, he nonetheless feels nostalgia for "fading memories / blending into dull tableaux."

The song, thanks in part to its video, which Priestley strongly supported and urged American networks to play, drew a notable level of attention in the U.S. Priestley also invited the band to play the song at the fictional night club, "The Peach Pit After Dark" on his series Beverly Hills, 90210. With some isolated exceptions, this was the band's first break into the American market, which continued with their next release, a live version of "Brian Wilson" from the ceritfied-gold album Rock Spectacle. The live version of "The Old Apartment" from that album was included on later American radio singles as a B-side option for stations.

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Wikipedia