on the case

on the case

1. Working diligently on a particular task. Our team of engineers is on the case to fix the issue, and we thank you for your continued patience with the matter.
2. Investigating something. When my youngest child thinks her older brother is doing something suspicious, she is always on the case—she's the best spy I could have asked for! Something went wrong with the engine, so I put my trusty mechanic on the case.
See also: case, on
References in classic literature ?
On one occasion I had an hour or so of a most intellectual conversation with a person whom I could not see distinctly, a gentleman from England, he said, with a cultivated voice, I on deck and he on the quay sitting on the case of a piano (landed out of our hold that very afternoon), and smoking a cigar which smelt very good.
A hearing on the case will begin on January 29, but a ruling is not expected before RAG's Degussa bid expires on January 31.
6% of the overall European business of the parties who are merging are in a single Member State, it is up to the national authorities to rule on the case.