Michael and Nadine are partners, both detectives with the Miami Police Department, working together to capture notorious drug dealer Sin Rostro. Following Jane ending her engagement to Michael, he quickly hooks up with Nadine and the two start having a casual relationship, while working on the case.
It is never actually specified when Nadine and Michael started working together, nor when they first met each other. When first introduced they banter a lot and seem to be competitive over the case regarding who solves it first. It's a sort of cat and mouse dynamic between them, which culminates in Michael kissing Nadine and them having sex in their office.
Throughout their investigation, in which they heatedly disagree and argue at times, they continue their sexual relationship, until Michael follows a lead in direct violation of his orders and ends up in the hospital. Nadine goes to see how he is and overhears Michael confessing his continued love to Jane. Nadine looks upset and subsequently reports Michael to their superior.
Michael accuses her of being jealous of Jane, which Nadine dismisses.
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