Robin was an English multi-millionaire industrialist, who spent most of his time on Cheers as a love interest for the gold-digging Rebecca Howe. This led to his developing something of a rivalry with Sam Malone because of Sam's own romantic interest in Rebecca.
Robin had a high sense of self-importance, was somewhat manipulative, and often made condescending remarks. He felt he could buy off anyone, which, at Cheers, often proved to be true.
In Season 8, Rebecca and Sam discovered that Robin was plotting a hostile takeover of the company for which they worked, and to aid him, had been secretly and illegally using Rebecca's access to the company's confidential information. Rebecca chose to conceal Robin's activities for the sake of their relationship. However, Sam discovered that the company suspected Rebecca of being a willing corporate spy. To protect her, Sam revealed Robin's crimes.
Amidst the ensuing scandal, Robin was arrested and briefly sent to prison as well as losing his business positions and money. He and Rebecca planned to marry on his release, despite his new humble status. She chose not to go through with this, after which he revealed he still had some of his fortune in a secret stash but that he would not marry her if she had only wanted his money. He appeared a final time in the last season claiming to be a broke vagabond, and a petty fugitive, and asking to reunite with Rebecca. The episode ended with him and Rebecca attempting to hitchhike out of town, Rebecca convinced this was a second test.