Ah, yes, but, you see, as Frank is washing the car and checking it over at the same time (like it Frank multi tasking, also shows that your character is not afraid to get in there with the turtle wax and the chamois leather, great, work that role baby!) he discovers that there is a large and suspicious looking package taped to the underside (cue dramatic music, camera cuts to close up of Frank's face., brow slightly furrowed, perhaps just a hint of a bead of sweat)
We can tell he's thinking. What is in the package? Is it a bomb? Is it drugs that the local Mafia are hoping that he might unwittingly transport to Edgbaston? Is it even.......... a large bundle of MONEY !
What should he do? Phone the police, phone the bomb squad, pay his council tax for the next 50 years?
If it is money than Frank can handle it, just treat it likely a slightly large London pension and everything's hunky dorey. But what if it IS a bomb?