The vessel, which will be powered by liquefied natural gas, will sail from Southampton on 7 August around the coast of its island namesake and the Scottish Isles.
Hadley is known for chart-topping singles such as ’True’, ’Gold’ and ’Through the Barricades’.
A "kaleidoscopic" firework display, from the island of Iona, will take place alongside aerial shows devised by Canadian entertainment company Creativiva.
Marco Pierre White and Olly Smith will offer food and drink "masterclasses" on board the 5,200 guest vessel.
P&O president Paul Ludlow said Iona’s maiden voyage will be a "momentous milestone" for travel.
