As a child, Hagen starred in a number of West end musicals, including Chitty Chitty Bang Bang at the London Palladium and as the voice of Control in the 2004–2013 UK tour of Starlight Express - The 3rd Dimension, on which her father, Peter Hagen, was musical director.
[2] Hagen starred in Britannia High as Lauren Waters alongside Mitch Hewer, Sapphire Elia, Matthew James Thomas, Rana Roy, Marcquelle Ward, Sophie Powles and Adam Garcia.
[3] Hagen has starred as Meat in the 2009/2010 UK tour of Queen musical We Will Rock You'',[1] and played the lead role of Pearl in Starlight Express in Bochum, Germany until May 25, 2014.
[4] She recently featured in Tim Minchin's new Musical 'Groundhog Day', in which she played the role of Nancy Taylor.
Hagen is the second cousin of Perry Fenwick, who plays Billy Mitchell in EastEnders.