Lucius Holly Laessig Jess Wolfe.

Singers Holly Laessig and Jess Wolfe have worked with a roster of greats in the two decades they’ve been together — people like Harry Styles, Brandi Carlile, Sheryl Crow, Jeff Tweedy and the Killers. They showed up for one of Joni Mitchell’s “Joni Jams” and performed one of Paul McCartney’s lesser-known songs for him. They played on tour in Roger Waters’ band. All those collaborations bring a danger, too, that they lose themselves and their own music in other people’s worlds. They self-produced and used the simple title “Lucius” for a new album, even though it’s their fourth disc, and say it feels like they’ve come home.