David Attenborough famously said the most fascinating creature on the planet is a nine-month-old baby. Scientists would agree, claiming nothing is more complex than the way babies grow and learn, and that studying them is the ultimate challenge.
This seemed like the perfect premise for a TV series. From the outset, our ambition was to create something that captured the wonder and complexity of babies and feature them in science experiments on a grand scale.
Our BBC commissioner, Craig Hunter, saw this as an opportunity to do science in a new way. Together we came up with the concept of a specially designed 'baby lab', where hundreds of babies would take part in experiments to answer some of the big questions about how we all develop.
It was clear from the moment the casting team posted their first call-out on social media that there was no shortage of subjects to film. The response was overwhelming.
As the application forms flooded in, we had two specialist factual APs wrangling with the science. They assembled a team of experts in baby science and scoured research journals for the latest studies on early development. We knew from early on that the tech would be critical to the experiments.
We sourced word-tracking devices to chart language development. We had a set designer build a puppet show to tease out babies' moral judgments and a five-foot-high cliff edge, covered in Perspex, to show what happens when babies learn to crawl.
The scientists designed caps embedded with electrodes to monitor the babies' brain activity, tantrum suits to record the physical effects of such outbursts and tests to assess how technology affects babies' development.