Harrison, who is being mentored by Glee and Broadway star Matthew Morrison, stands to win £50,000 and the chance to appear on Strictly Come Dancing later this year if he wins on Saturday.
He says: “I can’t even begin to explain how I’m feeling. It’s the most crazy, exciting time of my entire life and I can’t believe I have made it this far.
“I am feeling a bit nervous because it’s the final but I’m just excited to get onto that stage and give it everything.”
Harrison has been dancing since he was four and trains full time at Jennifer Ellison’s Jelli Studios in Edge Lane.
It’s Jennifer – who rose to fame as Emily Shadwick in Phil Redmond’s Channel 4 drama Brookside and who made her international film debut in the 2004 adaptation of The Phantom of the Opera directed by Joel Schumacher – who has been supporting and encouraging the young dance star who beat thousands to get into the competition and through to the final stages.
And it was she who choreographed Harrison’s audition piece for the top BBC One show, and has helped to create almost every move he’s made since.
Jennifer says: “His audition dance I created myself. Now, we get given a theme by the show’s producers and then we have to decide what we are going to do. I choreograph them, then the producers will have a say, and Matthew will have a say…”
At first, Harrison admits, he was nervous about working with A-list star Matthew, one of the show’s judges alongside Cheryl, Oti Mabuse and Todrick Hall: “Because he’s Matthew Morrison! How much has he done?!”
But he adds: “He is the most lovely, down-to-earth, humble person you will ever meet and, when I’m with him, I’m so relaxed. He’s the best dance captain you will have.”
Harrison, who has already appeared in the West End production of Matilda, wowed the audience and viewers with his first dance as a clown, but he is keeping his final performance under wraps until the night.
He will perform one of the favourite routines of the series, but he will also dance a newly-created routine and, Jennifer reveals: “He gets to dance with Matthew!”
Harrison has got a lot of supporters, but Jennifer is appealing to everyone in the city – and beyond – to get behind him, now he’s up against the other three finalists.
She says: “Liverpool needs to get behind him. We have got a big dance group from Scotland in the final with Harrison and we know Scotland really gets behind its acts, it’s fiercely loyal, so we really need Liverpool!”
You can get three free votes on BBCiPlayer, says Jennifer: “You don’t even need to pick up the phone.
“So please, get behind him and support our boy!”
The final of The Greatest Dancer: BBC One, Saturday, March 7 at 6.30pm.
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