 It was written by SM songwriter Kenzie and member Mark, whom went on to co-write three additional tracks in the album, while the former also worked with producer MZMC, singer-songwriter Bazzi, Mike Woods, and Kevin White on the song's production.Along with Mark, member Jeno, Jaemin and Jisung also took part in writing the lyrics for "Dear Dream", a hip-hop and pop song that memorizes the graduation of Mark from the sub-unit.The unit also worked with American production team The Stereotypes and Canadian musician August Rigo on the track "1, 2, 3", a funky R&B and dance-pop track that sings about falling for a new crush.