Recorded in secret during a year-long public silence, it is a concept album which explores mental health, suicide, and doubt, themes prominently featured in the band's previous works, framed in the metaphorical city of Dema and the surrounding valley known as "Trench".
Trench received acclaim from critics, who applauded its ambition, songwriting and more cohesive production; many contrasted it favorably with the band's previous album Blurryface. Several publications placed the record on their year-end lists, with Rock Sound naming it the best album of the year. It was also a commercial success, reaching number one in six countries, including Australia, New Zealand, Spain and the Netherlands, and number two in several countries, notably the United Kingdom and United States.