Def Leppard released their second studio album High 'N' Dry July 11, 1981, making it as high as #38 on the Billboard 200. The single Let It Go reached #34 on the mainstream charts. After the success of Pyromania, High 'N' Dry was rereleased in 1984. Bringin' On the Heartbreak was released as a single and and peaked at #61 on the U.S. charts.
So far, it has obtained double-platinum status in the U.S.
Def Leppard released their 4th studio album, Hysteria, August 3 1987, and has become their best-selling album to date. It has received critical acclaim from all over the world, selling over 12 million albums (certifying it diamond, i.e. >10M) in the U.S. where it reached #1 on the Billboard 200. Currently, it is the 51st best-selling album of all time.
According to Wikipedia, Q Magazine readers voted it the 98th Greatest Album of All Time. In 2004, Rolling Stone ranked it #464 on the list of the 500 Greatest Albums of all Time.
The album was released over 3 years after Pyromania, their breakout album, in 1983. Drummer Rick Allen lost an arm after a car crash in 1984. Producer Mutt Lange dropped out early in the album's production but returned a year later. Lange was also involved in an auto accident but recovered quickly and Joe Elliott suffered a bout of mumps. Still, they managed to pull off one of the greatest!
