Songfacts®:

• This song is about a stalker. The lyrics are very dark and go into detail about a guy with evil intentions, but the music is very light and catchy, which masked the meaning of the song. According to Blondie lead singer Debbie Harry, it was inspired by real events. She told Entertainment Weekly: "I was actually stalked by a nutjob, so it came out of a not-so-friendly personal event. I tried to inject a little levity into it to make it more lighthearted. It was a survival mechanism."
  
  Harry says that the title and the idea for the song popped into her head during a rehearsal, and most of the song was hashed out on the spot.
• Lead singer Debbie Harry wrote this song with the group's bass player, Nigel Harrison. Harry wrote the lyrics to Blondie's songs, but composer credit for the music was generally given solely to whoever made the biggest contribution. This was often guitarist Chris Stein, who co-wrote "Rapture" and "Heart Of Glass."
• This song has appeared in a number of movies and TV shows, often to imply dogged determination, not stalking. Here's a partial list:
  
  Movies:
  Little Darlings (1980)
  Donnie Brasco (1997)
  Beverly Hills Ninja (1997)
  The Rugrats Movie (1998)
  Coyote Ugly (2000 - Piper Perabo sings it to quell a riot in the bar)
  The Guru (2002 - performed by Sophie Ellis-Bextor)
  Mean Girls (2004)
  New York Minute (2004)
  Seed of Chucky (2004)
  Aquamarine (2006 - performed by Mandy Moore)
  Ready Player One (2018)
  
  TV Shows:
  The A-Team (1985)
  Sabrina, the Teenage Witch (1998)
  Queer as Folk (1999)
  Dawson's Creek (2002)
  The Simpsons (2004)
  Veronica Mars (2005)
  ER (2007)
  Psych (2008)
  Supernatural (2011)
• This was featured on a 2011 episode of the TV show Glee in a mashup with "Hit Me With Your Best Shot." The medley by the Glee Cast was released as a single and went to #86 in the US.
• With radio-friendly songs like this one, Blondie was one of the first Punk bands to have Pop success. They played clubs like CBGB's (stands for Country, BlueGrass, Blues) with bands like The Ramones and Television, but their songs were much lighter and led to mainstream acceptance. The Police and Talking Heads are other groups that came out of that scene.
• In 2013 the UK boyband One Direction recorded a new version of this song, mashing it up with The Undertones' "Teenage Kicks." It was recorded to mark the 25th anniversary of the fundraising event Red Nose Day and was a hit in both the UK where it topped the chart and the US where it peaked at #13.
• Kristen Bell sings this (quite well) at karaoke in the 2005 Veronica Mars episode "Clash Of The Tritons," where she uses the song to alert a gang of her intentions.
• Debbie Harry did a memorable version of this song when she was the guest star on The Muppet Show in 1981.