Dannii will host proceedings as Ronan Keating, Keith Duffy, Shane Lynch and Mikey Graham perform some of their biggest and best-loved hits, including 'Words', 'Father and Son', 'Picture of You' and 'Love Me For A Reason'.
They'll also be sitting down for a chat with Dannii to talk about the massive highs they've had throughout the years, and of course the crushing low of fifth member Stephen Gately, who passed away in 2009.
The band didn't always get on, and we're about to get a very revealing insight into their days on the road as youngsters as well as how they've matured and grown over the 20 years they've known each other.
Boyzone at 20: No Matter What, ITV, 9pm
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