Kathleen Johnson continues her nine-part collaborative fiction and sound project with “Brainchild, Part 4,” with composer and multi-instrumentalist Laura Steenberge at the Armory Center for the Arts in Pasadena, this Sunday, January 8, from 4 to 5 p.m.

For each successive part of Johnson’s sci-fi story, she collaborates with a guest composer who creates a choral work for performance. For Part 4, Steenberge has created a layered a cappella score for the waning daylight of the Armory’s art studio space.

Johnson’s narrative follows a girl, Brainchild, who discovers the abandoned structures of an ancient civilization, and slowly begins to understand her own strange connection to its builders.

In addition to “Brainchild,” Johnson’s practice has included photography, drawing, sculpture, and architectural collaborations. She received her BFA from Otis Art Institute and MFA from the University of Southern California.

Steenberge’s work considers the relationship between language and music, informed by studies of harmony, acoustics, perception, linguistics, mythology, and ritual. She has developed similar site-specific performances at the San Francisco Museum of Modern Art, the Hammer Museum, the Sutra Baths, the Cantor Arts Center, and other venues. She received her MFA from CalArts and DMA from Stanford University.

Sunday’s event is free. For more information, call (626) 792-5101 or visit www.armoryarts.org/visit/2017-events/brainchild4.

The Armory Center for the Arts is located at 145 N. Raymond Avenue in Pasadena.