Television
Mulhern began presenting on CITV in 1998. He co-hosted four series of Finger Tips with Fearne Cotton from 2001 until 2003 and with Naomi Wilkinson in 2004. He presented children's show Tricky TV from 2005 to 2010. He also co-hosted Holly & Stephen's Saturday Showdown (originally called Ministry of Mayhem) with Holly Willoughby from 2004 to 2006.
From 2006 to 2007, Mulhern hosted the ITV2 spin-off Dancing on Ice: Defrosted, while Phillip Schofield and Holly Willoughby hosted the main show.
From 2007 to 2019, Mulhern hosted ITV2 spin-off Britain's Got More Talent, which aired immediately after the main ITV show, which is hosted by Ant & Dec. Since 2013, Mulhern has become associated with the word 'unbelievable' which slowly became his catchphrase, usually used on Britain's Got More Talent as he walks offscreen at the end of a section, with Ant & Dec often mimicking him, and is also known for saying "Doosh!"
From 2009 to 2011, Mulhern narrated the ITV entertainment show Animals Do the Funniest Things.
Mulhern regularly presented inside 'The Hub', a small segment on the ITV daytime show This Morning. He most recently hosted the segment on Thursday and Friday mornings although had previously hosted on Wednesdays and Thursdays until the departure of Matt Johnson in the summer of 2013. Mulhern has occasionally presented the main show, standing in for the regular presenters.
In 2010, he hosted primetime game show Magic Numbers on ITV. Mulhern has hosted numerous episodes of The Big Quiz.
Since April 2013, Mulhern has presented a revived version of ITV game show Catchphrase. In September 2013, Mulhern began presenting ITV's Big Star's Little Star, a show which sees celebrities and their children compete to win up to £15,000 for charity.
On 27 October 2013, Mulhern began hosting a live Sunday morning show called Sunday Side Up on ITV. On 21 December 2013, Mulhern hosted entertainment special The Illusionists on ITV. On 14 September 2014, Mulhern guest hosted an episode of Sunday Night at the Palladium.
In early 2015, Mulhern presented the primetime ITV reality series Get Your Act Together. On 5 February 2015, he began presenting ITV2 panel show Reality Bites . In 2015, he presented The Magic Show Story a one-off special for ITV and The Saturday Night Story, a two-part series focusing on Saturday night television. In 2015, Mulhern presented Pick Me!, a daytime game show for ITV as well as ITV's annual charity telethon Text Santa. In March 2015, Mulhern became a victim of the Ant & Dec Undercover segment on Ant & Dec's Saturday Night Takeaway.
In February 2016, Mulhern became the presenter of the 'Ant vs Dec' segment on Ant & Dec's Saturday Night Takeaway after replacing Ashley Roberts. In 2016, Mulhern presented Go for It, and co-hosted The Next Great Magician alongside Rochelle Humes for ITV. On 12 April 2018, it was announced that Mulhern would host The National Lottery Draws on ITV.
In 2019, Mulhern presented In For a Penny, which is based on a segment he presents on Ant & Dec's Saturday Night Takeaway of the same name.
In August 2020, Mulhern began presenting a new game show on ITV, Rolling In It, featuring both contestants and celebrities. In February 2022, Mulhern guest presented Dancing on Ice alongside Willoughby whilst Phillip Schofield self-isolated from COVID-19. In January 2023 it was reported that a reboot of the show Deal or No Deal would be hosted by Mulhern airing from 20 November 2023. In December 2023, Mulhern was announced as the replacement co-host of Dancing on Ice, succeeding Schofield who resigned from ITV earlier in the year. Mulhern co-hosted Dancing on Ice from Series 16 in January 2024 to its cancellation at the end of Series 17 in March 2025.
