Profession: TV comedian and presenter
Pop star most like to imitate: Johnny Rotten or Frank Sinatra
Pop star that most resembles personality: Michael Buble
Biggest fear: Being a female. That is going to be hard. Anything that involves too much dance will be scary too
Did you know that once upon a time, Alexander trained as a classical singer? Apart from singing at a few friends weddings, he hasn't had much call for carrying on his hobby.
He says that even though he's used to being on stage, he's never taken part in a performance before, so is a little worried that his nerves may get to him.
Apparently, Alexander and his wife do a fantastic rendition of 'Up Where We Belong' but will we get the chance to hear his Joe Cocker, or Jennifer Warnes?
"I have never done anything quite where there is so much pressure but it is good to push yourself out of the comfort zone. I am really looking forward to taking part."
Alexander's charity: The Charlie Waller Memorial Trust
The Trust was set up in 1998 in memory of Charlie Waller, a young man who committed suicide whilst suffering from depression. Shortly after his death, his family founded the Trust in order to educate young people on the importance of staying mentally well and how to do so.
Over the years the Trust has grown into an independent charity that works with partners in the health service, education and the private sector across the country.
They also work with other charities and family trusts with similar aims and backgrounds.
Find out more