The reformed boyband, who will represent Britain at this year's song contest with 'I Can', have been criticised for their decision to enter the competition, but insist they are "excited" and "honoured" for the opportunity.
In a BBC documentary following the group as they prepare for the contest, Duncan James said: "The UK hasn't won Eurovision in 14 years. We like a bit of a challenge.
"To be part of something that is such a huge institution, this is a great opportunity for us."
Watch a preview below of Eurovision: Your Country Needs Blue, which airs this Sunday at 6.10pm on BBC One: