Adele has been seen filming a special guest appearance for James Corden's Carpool Karaoke as the late-night talk show host gets ready to end his show. After eight years of hosting the late-night talk show, the comedian is returning to the UK to pursue his love of theater. Adele sang some of her most famous songs in a black Range Rover SUV with James in Los Angeles on Tuesday (April 4). Since getting engaged to American sports agent Rich Paul, Adele has been composing and recording new music for the past year, motivated by love rather than sadness. A source told The Sun that Adele has been making "Her most upbeat and optimistic songs ever."