The Geordie duo, both 34, have a huge following in Ireland thanks to shows such as Saturday Night Takeaway, Britain's Got Talent and I'm A Celebrity... Get Me Out Of Here!, all of which are screened on TV3.
Lately, the two men have been hitting the publicity trail with a vengeance to promote their new book, with contains a host of private snaps of their lives.
Both of them starred as PJ and Duncan in long-running BBC kids' show Byker Grove. They then had a short-lived singing career, before forging ahead in TV.
Ant is married to Lisa Armstrong while Dec is now in a relationship with Sky Sports presenter Georgie Thompson.
The presenters are understood to be fending off offers from the States while developing ideas for new programme formats for ITV.
Joining the two lads on tonight's Late Late will be former chat show queen-turned-actress Ricki Lake.
Lake is in Ireland following her speech on behalf of the Home Birth Association of Ireland at a charity screening of her documentary, The Business of Being Born.
The Hairspray star hit the headlines in 2007 after releasing a particularly revealing film about her personal experiences of giving birth to her second child, Owen, at home in her bath tub in 2001, and also co-wrote a book on the same subject.
Tonight's show will be Tubridy's fourth as the new host of Late Late.
Guests who have been grilled by Tubridy include the Nolan Sisters, Kelly Osbourne, Jermaine Jackson and Brian McFadden.
Darren Sutherland's grieving father Tony gave a moving interview last week about his son, while Tubridy was praised for his tough interview with Taoiseach Brian Cowen in his debut programme. Ratings later showed that almost 1.6 million people tuned in at some stage of his first programme, making it the most watched Late Late Show, outside the Toy Show, since Gay Byrne's retirement in May 1999.
Rikki Lake's big night in Coolock, p24