It’s Easter and the biggest sales opportunity for supermarkets after Christmas. We meet Sandy and her supply chain team who have the difficult job of deciding exactly what to stock in each store and in what quantity. They base their decisions on a multitude of factors, including past consumer behaviour, current trends and up to the minute weather forecasts. With the British weather as unpredictable as ever, the supermarket needs to decide whether customers will be opting for the traditional roast this year or heading outside for a barbecue. A last-minute change in the forecast sends the team into a flurry of action to try to secure the extra stock needed before other retailers get there first.

Every year UK supermarkets generate 59 billion pieces of single-use plastic. While Greenpeace stage a demonstration at Sainsbury’s head office, the supermarket’s lab that deals with complaints is receiving more and more plastic through the post from unhappy customers. This episode follows the innovation team as they attempt to find a recyclable replacement for the plastic bag used to carry loose fruit and vegetables. As it is launched across the country, are customers ready for such a change in shopping habits?

At the clothing headquarters in Ansty Park near Coventry, it might only be April, but plans are already underway for this year’s festive wear. With the high street more competitive than ever, designs are being drawn up to cater for a new customer, the family dog. But with canines coming in all different shapes and sizes, it’s not as simple as one size fits all.

It’s the company’s 150th year of trading and to celebrate the supermarket is planning a party with a very special guest. This episode follows Head of Brand Communications Fleur and her PR team as they make preparations to welcome Her Majesty the Queen to their birthday event close to the supermarket’s very first site in central London. After 50 years’ service on the tills, Jenny from the Wallington store has been selected to meet the Queen, and she can’t wait.

In a suburb of Leeds, a new Sainsbury’s Local is being opened. Store manager Stephan and his team need to decide which products should be stocked to serve the well-off local community. How will the neighbouring shops on the parade react to the new competition?

While the supermarket celebrates its past, it’s also looking to the future by trialling an experiment to remove all the checkouts from one store, encouraging customers to pay for their items with their mobile phones. Will this unique trial change the face of shopping or simply send customers elsewhere?

It’s summer and with increasing numbers of Brits holidaying at home, it’s an ideal opportunity for Sainsbury's to cash in. Can key Cornwall stores Newquay and Bude take advantage or will the great British weather and the M5 ruin their plans? Bristol depot manager Mike battles with traffic to deliver enough products for the holidaymakers. In Penzance the fridges break down on one of the hottest days of the year.

Meanwhile, in HQ, product developer Charlotte is developing a vegan centrepiece for Christmas. But can she convince the press that her meat-free wellington is better than the competition?

All eyes are focused on the future, as Sainsbury’s embarks on an ambitious makeover of one of its biggest stores and the company tests out some of Britain's most exciting new food brands.

In Hedge End in Southampton, Manager Becky and her team try not to lose precious custom to their competitors, while the store undertakes a huge refurbishment.

At head office, the Future Brands team holds the fate of two food entrepreneurs in its hands. Dan’s chorizo snack and Andrew’s fresh fruit tea are being trialled across 70 stores, but the entrepreneurs must do their own marketing to secure sales. Will Andrew’s dinosaur-themed photo opportunity win the day? 

In retail, it’s never too early to start planning for Christmas, especially when it comes to the all-important Christmas ad. Senior Campaign Manager Laura is keen to recreate the success she had with her iconic World War One Christmas advert five years ago. But with the team struggling to nail the perfect emotional concept, is there a danger they’ll miss their chance to win customers' hearts and business at the busiest time of the year?

It’s Halloween and one of the last big sales opportunities of the year for Sainsbury’s. So, the pressure is on Emma and Martin from the produce team. They battle with wet weather to ensure this year’s crop delivers over a million pumpkins to stores. 

In the Locksbottom branch in Kent, Halloween could end up being a bit of a nightmare. The store has a low customer satisfaction rating and manager Mij is on a mission to retrain and reinvigorate his young team, in preparation for the big pumpkin push. 

It’s time to bring the Dickensian-themed Christmas advert to life, as Laura and Donna from the comms team head to Romania for the filming. They use state of the art neuro-testing to check the finished advert has all the emotion and brand-recognition to bring customers flocking to their stores, but the real test is how it compares to their rivals. 

To view more information about this programme and to watch the episodes, go to http://www.bbc.com/insidethesupermarket