‘Right, you go and fetch her, and let’s pray the traffic doesn’t ease while we try to work out how to lower my back seat so we can fit your bicycle in my nice clean boot.’

‘I’m telling you now that Betty is far cleaner than either of us currently are,’ I said.

Thankfully, it took less time than feared to get everything stowed, and when I clambered into the passenger seat, Brian’s vehicle was still in sight queueing for the exit.

‘Let’s get going,’ I said, making a note of his numberplate before hurriedly strapping myself in. I mentally apologised in advance to Leo for the grimy river water which was about to soak through from my underwear onto his pristine upholstery.

Leo set off at a crawl, slowly easing the car into the line of traffic, and steering it so we were slightly sticking out into the centre of the road where we could keep a watch on Brian about five vehicles ahead.

Fifteen minutes later, we were only halfway down the drive. A harried traffic marshal had informed us that there were three separate events happening at Blenheim today, and unfortunately everyone had decided to leave at the same time.

‘This is the worst car chase in history,’ I said, starting to laugh as we crept forward another couple of inches. ‘Maybe I would have been better on Betty, after all.’

‘Hmm, with that gold bicycle helmet of yours, he’d spot you a mile off. No, this is probably for the best. We’ll take it slowly and steadily and keep a couple of cars’ distance behind him once we do start moving properly. We don’t want to raise his suspicions when we’re following him.’

‘At least you’ve got a fairly nondescript car, so we won’t stand out,’ I said.

There was a sharp intake of breath from Leo. ‘I don’t insult Betty, so have the courtesy to do the same with Paolo.’

I laughed. ‘You gave me grief for naming my bicycle, then it turns out you’re equally as bad with your car. I knew you were a softy at heart.’

A sceptical ‘Hmm’ was his only response, but I thought I saw his lips twitch into a brief smile.

We finally emerged from the grounds of the palace and started moving at a decent speed.

‘How good are you at your Oxford geography?’ asked Leo. ‘Can you work out where he might be going while I concentrate on following him? If we can anticipate what his next move is, it’ll put us at an advantage and make it less obvious that we’re trailing him.’

‘I’ll try, but I don’t know this area of Oxford very well,’ I admitted. ‘And I’m better at bike routes than roadways.’

Fortunately, it wasn’t long before Brian turned towards more familiar territory.

‘I know where we are now. He’s not heading to the library, is he? What if he’s on to us and luring us back there to confront us?’

I worried I sounded ridiculous. But to give Leo credit, he took my suggestion seriously.

‘If he does stop at the library– and he’ll have a job finding parking around there, as I know to my cost– we’ll drive past, turn around in Wellington Square and you can ring whoever’s working today and tell them to keep a close eye on him if he goes into the building. I don’t think we’re anywhere near the confronting stage of our investigation, and if, or when, we do reach that, we’ll make sure it’s on our own terms.’

‘Moira’s in charge today. I’ll draft a text ready to send.’

We continued along St Giles’, but when we got to the traffic lights, they turned amber.

‘Oh, sod it,’ said Leo, accelerating suddenly so we managed to make it through before they went red.

We were just in time to see Brian manoeuvring around another corner further down the road.

‘He isn’t going to the library, phew. But I thought for a moment he was heading for the Randolph Hotel,’ I said. ‘He would have to be doing really well out of the scams to be staying there.’

After another few minutes of careful driving through the centre of Oxford, Brian indicated left and turned into a small car park, tapping something against the barrier to let him in.

‘We can’t follow him in there. It’s a private car park for the Oxford Grand,’ said Leo. ‘I’ll pull into the waiting bay opposite. I’m going to cause an incident if we stop here in the middle of the road any longer.’

‘I wonder what his connection to the theatre is? He obviously had a security pass to get him in there.’

‘We might be about to find out. Look, isn’t that him walking towards the stage door?’

We watched as Brian let himself into the building.

I sighed. ‘Now what are we going to do? We can’t follow him backstage, and they’re hardly going to let us in front of house in the state we’re currently in.’