In addition to being a radio presenter with RTE 2FM, McDermott is also the current M.C. for the Choice Music Prize, replacing Today FM radio presenter Paul McLoone who served as the previous M.C. for the main Choice Music Prize awards ceremony.
McDermott was born in Limerick, but grew up in Dublin. His father, Kevin McDermott, is an author.
McDermott is a fluent speaker of the Irish language and originally started his media career as an actor on TG4 youth drama Seacht, in which he played the lead role of Pete. From here he progressed to POP4, a weekly chart music show with live bands. Other presenting credits followed, including Frenemies - a youth debate game show for RTÉ2 and Immeal Geall, a bilingual magazine show for BBC Northern Ireland. He co-presented a series of The Movie Show on RTÉ2, which started in November 2012.
In 2008, McDermott entered MTV (UK and Ireland)'s Pick Me MTV competition, but lost out to Laura Whitmore.
In September 2013 McDermott had his UK television debut, fronting UK reality show Celebrity Super Spa for Channel 5. Other credits include a 2013 highlight show Totes Amazeballs and Next Year's News, a satirical comedy-panel show anticipating big news stories for the year ahead. Both shows broadcast on RTÉ2. He has co-presented The Voice of Ireland with Kathryn Thomas since its inception. For season 3 of The Voice, McDermott fronted a live spin-off show on RTÉ2. He filmed a new series entitled Drunk for RTÉ2 in summer 2014, examining the effects of alcohol on the body and mind.
In 2015, he hosted the Irish selection shows for the Junior Eurovision Song Contest 2015 (a role he continued in 2016), and filmed a pilot episode for a UK game show in Paris, which was made by the team behind Gogglebox.
McDermott has played the lead role of "DJ Pete" in all four series of the joint TG4/BBC Northern Ireland production, Seacht, a teen drama.
McDermott completed his dance training at the Broadway Dance Center and has worked as a dancer and choreographer, supporting acts such as Rihanna, Pussycat Dolls and Chris Brown.
McDermott started his radio career on a bi-lingual chart music show on Dublin radio station SPIN 1038 in 2009. He also co-presented the successful "Sunday Service" before being poached by Global Radio in the UK.
In March 2011 he began duties as host of Drive Time with radio station XFM. Xfm is known for finding and breaking presenting talent. Previous presenters have included Dermot O'Leary, Russell Brand, Alex Zane, Ricky Gervais, Simon Amstell & Jimmy Carr. In his first year, McDermott's show was syndicated to Xfm Manchester. Shortly after, he was nominated for "Best Newcomer" in the national commercial radio awards, sponsored by Arqiva. In April 2012, The Guardian newspaper - whilst discussing the new appointment of Greg James on BBC Radio1 Drivetime, claimed McDermott's show was the best DriveTime radio show of its genre in the UK.
His final show with the station aired on 21 December 2012. He said: "I left XFM because I had done it for two years. It is a great place to work with great people but I had had to turn down several pilots because of work. So I decided I wanted to focus on TV work and to do that I had to leave Xfm. And then I got this." It coincided with a management change and the departure of Mary Anne Hobbs to 6 Music and Breakfast presenter Danny Wallace - although in a Twitter post shortly after his departure McDermott noted his final listenership figures were a record high. Online speculation suggested a move to BBC Radio 1 although this has not yet materialised.
In June 2014, it was announced that McDermott would present a show on RTÉ 2fm radio on the 7-10am slot on Saturday and Sunday starting on 6 July. Three months later, it was announced that he would stand in for Louise McSharry on the station's weekday evening slot for the next few months while she receives treatment for cancer. In September 2015, McDermott took over from the Driveby show from Colm Hayes under a two-year contract.