Jess

Eventually, I find a fourth former police officer.

Initially, he says no, but after thinking it over, he agrees to talk because, he tells me, Jessica deserves some answers.

In his retirement, Oldwyn Jones sits on the committee of a village hall, and so we meet there.

He's a former detective chief inspector at Ipswich Police Station.

He's a tall, polite man with glasses and salt-and-pepper hair.

Babies are abandoned intermittently, but more often than not, it's their lifeless bodies that are later found.

Of the four babies abandoned in Suffolk in 1987, Jess was the only one found alive.

What would you have been looking for when you went to The Verge?

Aldwyn Jones visits the place where Jess was discovered just a few hours after she'd been taken to hospital.

And had you found a footprint or a tyre mark, what would you have done?

He tells me that any potential leads had been washed away.

In the first week, around 20 officers were on the case, doing house-to-house calls, manning the verge, running vehicle checks and monitoring a dedicated phone line.

It's the 1980s, remember, so the officers are working without any help from CCTV, computers or mobile phone records.

And investigations using DNA were in their infancy.

When the case paperwork arrives from Suffolk Police, it paints a picture of a pretty analogue investigation.

There's the appeal poster that was pinned up on notice boards across the county.

It carries a photo of Jess, taken in hospital when she's a day or so old.

She's wearing a pale crochet dress and next to her is a picture of the vest she was found in, with an Adams label showing.

Adams was a popular kids' clothing brand at the time.

I'm also sent two hand-drawn maps with a small cross marking the spot that Jess was found and several ordnance survey maps of the area with handwritten notes and markings on.