one after another; in succession
Describes things happening or appearing continuously, one right after the other. Often used with verbs of occurrence, movement, or change. Similar to 次から次へと, but 次から次に is slightly more common in everyday speech.
See also: 次から次へと
Problems kept happening one after another, and it was really tough.
彼は次から次に新しいアイデアを出してくる。
He comes up with new ideas one after another.
A set phrase composed of 次 (next) + から (from) + 次 (next) + に (particle indicating direction or state). The repetition of 次 emphasizes continuous succession.