Kahlo leaves for Paris after Diego realizes she was unfaithful to him with Trotsky; although Rivera had little problem with Kahlo's other affairs, Trotsky was too important to Rivera to be intimately involved with his wife. When she returns to Mexico, he asks for a divorce. In 1940, Trotsky is murdered in Mexico City. Initially, Rivera is suspected by police of orchestrating the assassination. After they fail to locate him, Kahlo is imprisoned in Rivera's place. Cristina arrives and escorts Kahlo out of prison, explaining that Rivera convinced President Cárdenas to release Kahlo.