Started in 1983, the Two California Plaza tower was completed in 1992 during a significant slump in the downtown Los Angeles real estate market.

California Plaza was originally planned to include three high rise tower office buildings instead of the two completed.

[8] Three California Plaza at 65 floors, was planned for a site just north of 4th Street, directly across Olive Street from California Plaza's first two office highrises[9] and was planned to house the Metropolitan Water District's permanent headquarters.

[10] The construction and $23 million cost of the MOCA Grand Avenue building was part of a city-brokered deal with the developer of the California Plaza redevelopment project, Bunker Hill Associates, which received the use of an 11-acre (4.5 ha), publicly owned parcel of land.

[11][12] One California Plaza was purchased on June 6, 2017 by a partnership between Rising Realty Partners and Colony Northstar, Inc.[13] Tower One was featured in the Nickelodeon television show Drake & Josh as Spin City Records in the episode "Really Big Shrimp".