Theatre in a Trunk was a theatre company in Boise, Idaho from 1972-1978. Founded by Boise State College (now University) theatre arts students and graduates, the company began as an itinerant troupe that performed throughout the region from Boise State's campus to Sun Valley and McCall, Idaho. In 1974 the group sub-leased a warehouse space from the Intelist Corportation on 17th and Bannock Streets in Boise. Company members converted the warehouse into a 70-seat performace space, and became known as the "resident" company of the Intelist Theatre. Under the direction of Randy Krawl, Theatre in a Trunk produced modern and classic plays. Depsite local acclaim, the company ceased production in 1978 due to financial hardships, unable to meet their original goal of paying the cast and crew.

In late 1978 and early 1979, company members David Bogie and Pamela Abas organized public screenings of a slide presentation titled, "Theatre in a Trunk: a Retrospective" featuring Bogie's photographs. The Idaho Statesman called it a "fitting burial for Trunk," as a company that, "provided a stage for some of Boise's brightest actors and directors." Multiple members of Theatre in a Trunk went on to help establish the Idaho Shakespeare Festival beginning in 1977.