An idiom meaning a rapid change from a very good situation to a very bad one — 'from heaven to hell.' It emphasizes a dramatic reversal.
昇進して嬉しかったが、すぐに問題が起きて天国から地獄だった。
I was happy about the promotion, but problems arose quickly and it was like going from heaven to hell.
試験開始直後は簡単だと思ったが、途中で難問が出て天国から地獄のようだった。
At the start of the exam I thought it was easy, but a hard question appeared midway and it felt like going from heaven to hell.
結婚生活が天国から地獄に変わるケースもあるので注意が必要だ。
There are cases where married life changes from heaven to hell, so caution is necessary.