And it is easy for Sean to get his revenge since Alexis is so quick to integrate Sean into her family and her empire. Determined to stop Blake from becoming Governor (jealousy perhaps?), Alexis runs for Governor herself and puts Sean in charge of Colby Co since her three children (remember, Amanda has ceased to exist) are co-running Denver Carrington. Alexis never put Dex in charge of Colby Co and Dex is a far better business person than Sean. Sean, of course, uses the power to enrich himself and sow seeds of discord among the Carrington siblings.
But, Sean is not done. To keep Alexis from dropping out of the race, Sean tries to assassinate Blake (would it not be easier just to kill Alexis at this point since that is Sean’s ultimate goal). Alexis takes the bullet which revives her campaign (did Alexis even run on an issue?) which, ironically, helps him retain control at Colby Co. He seduces Leslie, blackmails Dana, and interferes in Adam’s adoption of his son by bringing back the estranged husband of the surrogate mother. I am surprised he didn’t sell the drugs to Josh before Josh ODed or try to convince the aliens to abduct Fallon again.
Even after everyone learns the truth about Sean, his reign of terror does not end. He tries to kill Blake and Dex in Africa; kidnaps Adam’s baby and beats the hell out of Leslie (is Leslie still in that cabin?) before he finally is able to confront Alexis one last time. Of course, Dex is there to save Alexis and Sean is finally killed.
Revenge is a common theme throughout Dynasty - especially to avenge a wronged family member. Blake had to deal with members of the Grimes family, Jason had to deal with Zach Powers, and Alexis had to deal with the Anders family (among her several enemies).