Trace is an installation by Ai Weiwei that is representative of individuals who have been imprisoned or exiled because of their actions or affiliations. Visitors are met with 176 colorful portraits, constructed from LEGO bricks, that are laid across the floor. Each portrait symbolizes an individual who can relate to the message at hand. The significance of this theme is furthered as the location of the installation is at the New Industries Building at Alcatraz Island in San Francisco, California. Ai Weiwei is a Beijing-based artist and activist that combines multiple mediums of art and social criticisms.