It promises to be a night of sequins and high drama.

Tomorrow, millions will grip the edge of their sofas as they watch the final eight couples battle it out for the covetedGreatly desired or envied. It originates from the Latin cupiditas, meaning eagerness or ambition.  Strictly Come Dancing glitterball. Can Tilly and Nikita avoid the dance-off? Will Rose and Giovanni, the earliest couple ever to score top marks, repeat their perfect performance? 

It is not just in Britain that viewers are hooked. Strictly is the world's most successful reality television format. It is broadcast in more than 75 different countries, including the USA, India and China.

The show has a reputation for glitz, glamour and celebrity sagas. Few could forget politician Ann WiddecombeA Conservative MP (1987-2010), she became a Brexit MEP in 2019. She has appeared on Strictly Come Dancing and collects soft toys. being dragged across the floor like a "lame canary", or the 57 litres of fake tan doused on contestants every series. 

Could Strictly have a purpose beyond entertainment?

This year, EastEnders actress Rose Ayling-Ellis is breaking records both on and off the dance floor. In week six, the first deaf UK contestant wowed audiences by incorporating sign languageThe BBC purposefully did not add subtitles to help people who do not know sign language understand how deaf people often feel.  into her Viennese Waltz. Since then, the number of people searching online for sign language courses has rocketed by an incredible 488%.

Strictly is "a good chance to break the stereotype of what deaf people can and cannot do," Ayling-Ellis told reporters. "Deaf people will have a better experience." 

In 2020, boxer Nicola Adams and dancer Katya Jones made headlines as the first same-sex dance partnership. This year, Bake Off winner John Whaite and partner Johannes Radebe are the first all-male pairing. 

"John and I dancing together stands for something far bigger than we actually realise," says Johannes. "It will go a long way towards changing attitudes."

Meanwhile, chef Gordon Ramsay has praised his daughter Tilly as a "role model" after she stood up to a DJ who made negative comments about her appearance. 

And it is not just Strictly that can break down boundaries. In 2012, one US study found that students who watched films depicting altruistic acts had a greater motivation to do good things for others.

Academics point out that soap operas and television shows have a long history of fostering social change. 

The Archers was created by the UK Ministry of Agriculture in 1951 to encourage farmers to try new, more productive techniques. 

In the 1960s, Black actress Nichelle Nichols' interracial kiss on Star Trek was so instrumental in changing racial attitudes in the US that Martin Luther KingThe civil rights leader was shot dead in Tennessee in 1968.  Jr persuaded her to stay in the role. 

More recently, in 2017, scientists hailed the "Blue PlanetBlue Planet II was the fourth most popular TV programme of all time in the UK. effect" after David Attenborough's documentary on ocean pollution prompted 88% of viewers to change their habits. 

"Nobody who watched Blue Planet will doubt the need for us to do something," declared then UK Prime Minister Theresa May.

"In the end, we are all changed by what we see," summarises broadcaster Trevor McDonald. "Just as we are changed when we are seen." 

No, say some. In Norway, scientists have linked the introduction of television to a decline in the average national IQ. Shows like Strictly Come Dancing are created to provide mindless entertainment. They reflect societal change, but they do not create it.

Absolutely, say others. The thousands of new sign language students means Rose Ayling-Ellis's Strictly appearance has already left a lasting legacy. Representation in popular entertainment shows has helped change societal attitudes on race, gender, sexuality, mental health and more. There is no doubt: TV can change the world for the better.