There's a strong pop flavour to bespectacled comedian Alan Carr's green room tonight. The cheekily probing host's guests are pop singer and The Voice coach Jessie J, discussing her autobiography Nice to Meet You, tousle-haired, America-conquering boy band One Direction - so brace yourself for hormonal screams from the studio audience - and US soul diva Alicia Keys, who will also be performing. The line-up is completed by Kevin McCloud, whose new series of Grand Designs is currently being shown on Channel 4.