The first One Show of 2019 has James Norton and Tom Brittney talking to Matt Baker and Alex Jones about the latest series of Grantchester. Carrie Grant reports on a new groundbreaking nut allergy trial and Joe Crowley is live from Ironbridge in Shropshire as the Iron Bridge reopens.

Clare Balding and Sanjeev Bhaskar launch a vote to find the most important and influential figure of the 20th century. They tell Matt Baker and Alex Jones who has made the final Icons shortlist and how viewers can choose their favourite. Dame Kelly Holmes describes hitting rock bottom after injury threatened to destroy her career, while JJ Chalmers celebrates the New Year in a risky and unusual location.

Matt Baker and Alex Jones are joined by Stan & Ollie stars Steve Coogan and John C Reilly, and the creators of hit sitcom Catastrophe Sharon Horgan and Rob Delaney. Plus former Elbow drummer Richard Jupp meets a new band close to his heart, and we borrow a cathedral in Ireland to play a very familiar theme tune.

Saoirse Ronan is in the studio to discuss her role as Mary Queen of Scots, and The One Show reveals the results of the BBC's search for the greatest person of the 20th century.

Alex Jones and Michael Ball talk to Zoe Ball ahead of her taking over the reins as the breakfast show host on Radio 2. Fleur East reveals what life is like after I'm a Celebrity and performs her new single, Favourite Thing, live.