Guitarist Bill Kelliher told The Skinny magazine that this song, "has got a crazy melody with an even crazier guitar riff in the beginning there 'badda-doodle-noodle-badda-badda-noodle-noodle…' a lot of notes going on. When we were tracking that song, I came up with the guitar riff that goes under the main vocals and the really busy guitar part. So when Brent was singing and playing it he said 'I can't play the fast parts, we're going to have to switch so I can sing and play. You can play the crazy riff.' I didn't think I could really do it, it's all in his styling and it's a very chicken-pickin' kind of playing style. But I got it down and it took a minute. That was basically all for the sake of playing it live."
Quintessence is a hypothetical form of dark energy; by which scientists attempt to explain the accelerating universe. It was originally a fifth element postulated by the Ancient Greeks in addition to their understanding of the four existing elements of earth, air, fire and water. They believed the cosmos and all celestial bodies were made of this element. In the song the principal character of the storyline, who has had an out of body experience, gets sucked into a wormhole.
"Thinking About You" was the ninth track from Calvin Harris' 18 Months album to enter the UK singles Top 10. No other artist has obtained so many hits from one LP - Michael Jackson was the previous record holder with seven Top 10 tunes from both his Bad and Dangerous sets.