Mariana (Mariana Seoane) and Julián (Plutarco Haza) are a successful, happily married couple with children who seem to have an ideal life. To keep their passion alive and avoid secrets, they make a mutual agreement to open their marriage with one strict rule: complete transparency about any extramarital encounters. However, when Mariana engages in a passionate relationship with Javier Betanzos (Humberto Zurita), a charismatic older businessman, Julián's unresolved jealousy, possessiveness, and emotional insecurity threaten to destroy their marriage.