[1] He previously presented current affairs television programme Prime Time from 2013 to 2020,[2] and was political correspondent with RTÉ News.
[2] In 1999, he won a prize under the category 'TV features and documentaries' in the ESB national media awards.
[8] He has also written the book A Makeshift Majority: The first inter-party government, 1948-51,[6] and a biography of John A. Costello.
[10][11] In September 2022, McCullagh was named as one of four presenters to host Monday Night Live, a new eight-part current affairs panel series on RTÉ One, beginning on 3 October.
[12] McCullagh attended Newpark Comprehensive School and studied politics in University College Dublin.