John Lewis Christmas advert: Monty the Penguin stars as Tom Odell covers John Lennon

The advert is part of a £7m festive store campaign

A scene from the 2014 John Lewis Christmas advert

Sam is a cute little boy who has an even more adorable penguin friend, Monty. They pair are inseparable, playing football and hide and seek together. But Monty is sad because he wants a “special friend”.

So on Christmas Day Sam gives Monty the gift he has been dreaming of, a new penguin friend called Mabel, as a tremulous rendition of John Lennon’s Real Love swells to an emotional peak – and a viewing nation dissolves in floods, then heads straight off to John Lewis to buy their pre-lit paper birch Christmas tree, available for just £125.

Now an annual event akin to Glastonbury and Wimbledon, the new John Lewis Christmas advert “breaks” today with the social media premiere of Monty’s Christmas, the £1m sequel to last year’s equally heart-rending epic, The Bear and The Hare.

That woodland scene, accompanied by Lily Allen’s “haunting” cover of Keane’s Somewhere Only We Know, is credited with helping boost John Lewis’ sales by 6.9 per cent on the previous year.

The 2014 offering, created by advertising agency Adam&Eve/DDB, does not stray far from a shamelessly sentimental formula. The two-minute Monty’s Penguin clip evokes “the magic of make-believe at Christmas through a child’s eyes,” the retailer said.

No John Lewis festive film would be complete without a hushed, melancholic trudge through a popular song. After a nationwide search, the hand of fate has fallen upon Tom Odell, the Chichester singer-songwriter who can expect a chart-topping boost from his reworking of an overlooked Lennon song, revived by The Beatles for their 1995 Anthology collection.

Behind the clip’s heartwarming glow and the “Give someone the Christmas they’ve been dreaming of” strapline, the John Lewis advert signals the launch of a retail battle for “eyeballs” over the festive season.

Pick up a penguin: John Lewis’s emotional ‘story’ is part of a £7m festive store campaign (PA)

Burberry has delivered a pre-emptive strike with its From London with Love campaign, which features a 12 year-old Romeo Beckham, swaddled in a Burberry scarf and trench coat, playing cupid to a young couple. The advert has been viewed 2.3m times online since Monday.

Waitrose, despite being part of the John Lewis group, is hoping to steal the “most talked-about Christmas advert” crown, with an emotive charity single, featuring community choirs and singers performing a version of Dolly Parton’s Try.

Sainsbury’s is expected to reveal an advert which focuses on the famous football match that took place between British and German forces during Christmas 1914, to mark the First World War centenary. The insurgent Lidl is targeting M&S and Waitrose customers with an “I can’t believe its Lidl” Christmas campaign.

John Lewis, which recorded a 44.3% online sales surge after its 2012 tale of a snowman making a perilous journey to buy a hat and gloves for his snowwoman companion aired, has been forced to up its game.

Monty’s Penguin, part of a £7m festive store campaign, has Hollywood pretensions. Monty and Mabel have been created using complex CGI technology “to look and behave exactly like real life Adélie penguins.”

And so John Lewis, which recorded a 44.3 per cent online sales surge after its 2012 tale of a snowman making a perilous journey to buy a hat and gloves for his snow-woman companion aired, has been forced to up its game.

The advert will be supported in stores by “Monty’s Goggles”, which use Google Cardboard to allow children to “enter a 360° virtual world and interact with Sam and Monty.”

There will be Monty and Mabel merchandise, including a “cute as cute can be” £21 penguin-covered onesie. The penguins’ back-story will be told in a children’s book, which is also available on iTunes as an audio app, narrated by Dermot O’Leary.

Fame beckons for Rhys from Hertfordshire, the 7 year-old boy chosen to play Sam. A screen veteran, who won his first TV role aged 5, Rhys was praised by director Dougal Wilson for his “extremely expressive and very endearing” performance.

Craig Inglis, Marketing Director at John Lewis, said: “We hope this uplifting tale of Sam’s love for his friend Monty will remind people of the magic of Christmas through a child’s eyes and inspire them to think how they can make the festive season extra special for their friends and loved ones.”

Wiping away a tear, Inglis added: “We hope our customers will have more chances than ever to interact with them through some genuinely exciting technology firsts.”

The last people to see the television advert, after its merits have been thoroughly debated on Twitter today (#MontyThePenguin) will be actual television viewers. The full 120-second version will air on Friday during the first advert break in Channel 4’s Gogglebox and will no doubt be chewed over by the series’ couch potatoes the following week. If they aren’t reduced to a moist-eyed mess then Christmas is well and truly cancelled.