The Book of Us: Entropy

On September 28, 2019, it was reported that Day6 would be returning with new music in October after fans discovered an advertisement at a subway station depicting Day6's logo with the date October 22 and the time 6 pm. Day6's agency JYP Entertainment later confirmed, "it is true that Day6 will come back on October 22".{{Cite news|url=http://www.topstarnews.net/news/articleView.html?idxno=676117|title=[팩트체크] 데이식스(DAY6), 10월 22일 컴백…JYP 측 "자세한 사항은 추후 공개"|last=Kim|first=Hyo-jin|date=September 30, 2019|work=topstarnews|access-date=October 29, 2019|language=Ko}} On October 6, 2019, a prologue film entitled The Book of Us: Entropy was released on Youtube. Pre-orders for the physical album opened on October 7, it became available in two versions: "Sweet" and "Chaos". On October 8, 2019, the tracklist was released, consisting of 11 new tracks. On October 10, individual "graphic image" teasers for each member were released. Following that, a series of individual and group photo teasers were revealed from October 11–20. The first music video teaser for the lead single "Sweet Chaos" was released on October 20 and an album sampler was revealed the following day.{{Cite news|url=https://n.news.naver.com/entertain/article/109/0004105915|title=데이식스, 오늘(22일) 정규3집 컴백..11트랙 모두 명곡 예감[공식]|last=Sun|first=Mi-kyung|date=October 22, 2019|work=Osen|access-date=October 29, 2019}}{{Cite news|url=https://n.news.naver.com/entertain/article/408/0000079797|title='컴백 D-DAY' 데이식스, 샘플러 영상 공개! 11개 트랙 모두 명곡 예감|last=Cha|first=Hye-Mi|date=October 22, 2019|work=MBC|access-date=October 29, 2019}}

Musically, the rock album incorporates several retro music genres including glam metal, disco, bossa nova and reggae.{{cite web|url=https://en.yna.co.kr/view/AEN20191022008900315|title=DAY6 returns with 3rd full album 'The Book of Us: Entropy'|date=October 22, 2019|accessdate=April 25, 2020|last=Park|first=Boram|work=Yonhap News Agency}} The lead single, "Sweet Chaos" has been described as a swing number that combines groove with punk rock.{{cite web|url=https://entertain.naver.com/read?oid=469&aid=0000432982|last=Jeong|first=Han-byul|script-title=ko:데이식스, 오늘(22일) ‘6시 5분 전’에서 새 앨범 소개|trans-title=Daysix introduces new album at '6:05 ago' today (22nd)|work=Hankook Ilbo|date=October 22, 2019|accessdate=April 25, 2020|language=ko|via=Naver}} Talking about the album, Young K explained that The Book of Us: Entropy "features the process of changes a person's relationship with another person weaves." He further added, "The process is sometime heartwarming, but other times, it's chilling." Thematically, the album explores "the chaotic but dazzling entrance into a romantic relationship and chilling exit that follows."

{{Track listing

| all_writing =

| title1 = Deep in Love

| length1 = 3:47

| title2 = Sweet Chaos

| length2 = 3:47

| title3 = Emergency

| length3 = 3:18

| title4 = Rescue Me

| length4 = 3:22

| title5 = 365247

| length5 = 2:53

| title6 = About Now

| note6 = 지금쯤

| length6 = 2:59

| title7 = Ouch

| note7 = 아야야

| length7 = 3:17

| title8 = Not Fine

| length8 = 3:36

| title9 = Stop Talking

| note9 = 막말

| length9 = 3:47

| title10 = Not Mine

| length10 = 3:16

| total_length = 37:25

| length11 = 3:23

| title11 = Like a Flowing Wind

| note11 = 마치 흘러가는 바람처럼

| lyrics1 = Young K

| music1 = {{hlist|Jae|Sungjin|Young K|Wonpil|Hong Jisang}}

| extra_column = Arrangement

| extra1 = Hong Jisang

| lyrics2 = Young K

| music2 = {{hlist|Jae|Sungjin|Young K|Wonpil|Hong Jisang}}

| lyrics3 = {{hlist|Jae|Shim Eun Ji|Lee Hae Sol}}

| extra2 = Hong Jisang

| extra3 = {{hlist|Shim Eun Ji|Lee Hae Sol}}

| music3 = {{hlist|Jae|Shim Eun Ji|Lee Hae Sol}}

| lyrics4 = {{hlist|Young K|Wonpil}}

| music4 = {{hlist|Jae|Wonpil|FRANTS}}

| extra4 = {{hlist|Shim Eun Ji|Lee Hae Sol}}

| lyrics5 = Young K

| music5 = {{hlist|Young K|FRANTS}}

| extra5 = FRANTS

| lyrics6 = {{hlist|Jae|mr. cho}}

| music6 = {{hlist|Jae|mr. cho}}

| extra6 = mr. cho

| lyrics7 = Young K

| music7 = {{hlist|Young K|Nuplay (KIME, MHL, Jo Chang Hyun)|Sean M. Sinclair}}

| extra7 = {{hlist|Nuplay (KIME, MHL, Jo Chang Hyun)|Sean M. Sinclair}}

| lyrics8 = Young K

| lyrics9 = Young K

| lyrics10 = {{hlist|Wonpil|Jeon Da Sol|Jae Do Gi}}

| lyrics11 = {{hlist|Young K|Wonpil}}

| music8 = {{hlist|Jae|Sungjin|Young K|Wonpil|Hong Jisang}}

| music9 = {{hlist|Jae|Young K|Nuplay (203, Swavey Child)}}

| music10 = {{hlist|Wonpil|Jeon Da Sol|Jae Do Gi}}

| music11 = {{hlist|Wonpil|Kim Yeon Seo|minGtion}}

| extra8 = Hong Jisang

| extra9 = 203 (Nuplay)

| extra10 = Jeon Da Sol

| extra11 = minGtion

}}

{{reflist}}

{{Day6}}

{{Authority control}}

{{DEFAULTSORT:Book of Us Entropy}}

Category:2019 albums

Category:Day6 albums

Category:2010s Korean-language albums