Olympic gold medallist Jessica Ennis-Hill, who was hidden from view, gave those who visited the child-sized ATM fun tasks to complete.
The ATM then deposited participants a gift, along with cash to help families over the Christmas period. Select customers also got the chance to meet Ennis-Hill in person, when she exited the booth to present them with Christmas hampers.
The experience, which took place at the end of November, was captured via a number of hidden cameras positioned around the ATM.
The footage has since been created into the bank's Christmas 2015 advert, which was created by David Stoddart and released yesterday (8 December). It features on television and online, and is designed to thank everyone who banks with Santander.
Engine Group agency WCRS is behind the activation’s creative, meanwhile Slice, also a part of Engine, built the ATM.
Keith Moor, chief marketing officer at Santander, said: "Christmas is a fantastic opportunity to say thank you to our customers and give something back. Jessica is a British sporting icon, and it was great to have her involved in helping to surprise and delight people in Barnsley as Santander’s Secret Santa."
Billy Faithfull, executive creative director at Engine, added: "There’s nothing like a little magic sprinkled on something as functional as a cash machine to spice up a cold afternoon on the high street.
"You never know what you’re going to get with this sort of thing, but that makes it all the more fun to film, with kids doing the robot, dads doing the worm and the genuine delight of people getting something a little more out of their bank."
Last Christmas the brand enlisted Jenson Button for a similar stunt, where members of the public were encouraged to 'push the Jenson Button to continue', at which point they received £100 in cash and a Christmas hamper.
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