Some kind of very young tech genius has the highest of security clearances to be able to do their work. But their work is so specialised that they aren’t needed too often. Think defusing nuclear bombs or something. Crypto ransoms… Doesn’t matter much.
Turns out there is an inter-agency initiative to match up under-utilised staff with other departments ad hoc.
So our hero gets send to random scenarios, knowing almost nothing about what is going on, and is given tasks often not-highly-related-to-their-skillset. For example, “you know tech, right?”.
They will need a quirk of course, and it cannot be being a junior, or autistic, or OCD, or psychic.
Old, perhaps.
Ex-con, maybe
Double agent is possible
Or super-hero who uses this to get things to do