'It's the one I always come back to', ‘It makes a visible difference’ and 'I swear by it' are just a few of the comments I have picked up at an editors’ lunch here or a press launch there.

This autumn, Estée Lauder has reformulated their classic serum so it performs better than ever – and it hits counters today. At 5 o'clock this afternoon, there'll be a synchronized launch of Advanced Night Repair Synchronized Recovery Complex (£36 for 30ml) nationwide and you’ll be able to get a week’s trial supply for free if you get there before the crowds.

So what’s improved? ANR was always based on the idea that the skin repairs itself at night, but now that technology has been turned up several notches. New research has shown that the sequencing and timing of the skin’s self-repair mechanisms are synchronized by a series of ‘clock genes’, present in each skin cell. With age and repeated exposure to environmental stresses, these clock genes can become out of sync, causing protective processes to slow down and compromising DNA repair. Inspired by this knowledge, ANR now includes something called Chronolux technology, which targets these clock genes and supports the synchronization of skin's own repair mechanisms. The result is an increase in the skin's ability to improve its own appearance. That’s the theory, anyway.

But as with all new skincare launches, it doesn’t matter how much science brands throw at their products, and then at us, the consumers – ultimately, the proof of the pudding is in the regular application of your chosen product. In other words, the most accurate clinical trial is the one you do on yourself.

You can test ANR for free by picking up a week’s supply at your nearest Estée Lauder counter, or buy full-size and get a free Sleep Kit with your purchase. ‘It’s adorable,’ the PR for Estée Lauder assured me. ‘It contains a silk eye mask, chamomile tea bags and a solid hot chocolate stick.’

You’d better make it at 5 on the dot, though – there’s a limited supply.

Click here to visit the Estee Lauder website