This ‘based on a true story’ is more based on a true story than most. My wife has been quite unwell for a while and the parade of doctors has gotten us no closer to a diagnosis. A referral to a specialist in multiple branches of medicine ended with the doctor saying ‘I don’t know and I’m not going to look any further’.
I tried to come up with other jobs where it would be acceptable to give this sort of answer, so obviously mechanic.
The mechanic ended up looking like Mario from Super Mario Bros (or perhaps Dr Mario), so I just went with it.