When rockers Marianas Trench perform at Interior Savings Centre on Saturday there will be 16 to 18 local high-school voices backing them up for a song or two.

"Just seeing Marianas Trench will be like some little girl spending their day with Justin Bieber," said self-proclaimed fangirl Brook McLean.

"I just absolutely love Marianas Trench."

So much so that McLean was willing to scale a three-storey building last year after she got locked out of an apartment that tickets were in.

Getting to sing on stage with the band during the Kamloops show proved more of an organization challenge than a physical one.

McLean said there's a contest in every city or town Marianas Trench performs where the winner joins the band on stage. When the Grade-11 South Kamloops secondary student heard about this, she was determined to win.

She almost didn't see the fan club email because of a car accident, she said. In the end, she had four days to put the video audition together.

She asked her school choir if anyone was interested but only 12 of the 56 boys and girls wanted to participate. Fortunately, word quickly spread and her "choir" grew, she said.

With some choreography by Beattie School of the Arts student Katjana Johnson, the group sang and danced to Marianas Trench songs Fallout and Stutter. Musician Kris Ruston helped produce the project.

The audition was submitted on Sept. 24. A week and a half later 604 Records emailed McLean with word her choir had won.

The students will be at the ISC at 3 p.m. Saturday for rehearsal. They get to meet the band — Josh Ramsey, Mike Ayley, Matt Webb and Ian Casselman — at 6:15 p.m. and wait in the greenroom until their big moment arrives.

Johnson, also in Grade 11, looks forward to meeting her favourite band.

"They are really a lot of fun and really great," she said.

Saturday's show begins at 7 p.m.

Down With Webster and Anami Vice open for Marianas Trench.