Red Light is the third full album by F(x), released on July 7, 2014 with "Red Light" serving as the album's title track. The track "Milk" was also used during promotions.
The album was physically released in two versions: a type A version called "Sleepy Cats" with 2 different covers (randomly printed either on the front side or the back of the case) and a type B version called "Wild Cats".
The album's concept is darker than the ones the group has shown before. The members expressed their happiness of being able to show another side of them in various interviews.
The title track "Red Light" is described on Korean digital platforms as a "blast of urban rhythm bit, reversal in electrohouse genre". The lyrics talk about capturing great moments, stop and reconsider what is important in life. It is a also message, using "red light" to symbolize the warning.
It was later clarified by SM Entertainment's director of production Lee Sung Soo the meaning behind the song as being a criticism of the Sewol ferry's incident that happened earlier in 2014 in South Korea.
1. Red Light
5. All Night
7. Spit It Out
8. Boom Bang Boom
10. Summer Lover
11. Paper Heart
IV. MV and Album Tracks