Dean first appears at the beginning of the movie where he and Eggsy's mother Michelle, are sitting on the couch in front of the television when Eggsy comes in. Dean suggests Eggsy to buy some Rizlas, but Eggsy tells Dean "Get them yourself." and Eggsy is scolded Michelle for speaking to Dean like that. Dean then gives Eggsy the money to buy the Rizlas.
When Eggsy returns home the next day, Dean ambushes Eggsy and beats and interrogates him on the man responsible for attacking his gang, but Eggsy doesn't give in. Dean then threatens to kill Eggsy with a meat cleaver, but is saved by the timely intervention of Harry Hart, who bugged Eggsy's vest with a tiny microphone. Perplexed as to where Harry's voice is originating, Eggsy escapes Dean's grasp and flees to become Harry's candidate to become a Kingsman agent.
After Eggsy save the world from Richmond Valentine, he becomes a Kingsman agent and offers his mother a new home away from Dean, but Dean orders Michelle to sit down and gets up and threateningly tells Eggsy "Only place she'll be visiting is you in f***king hospital, do you hear?", only for Eggsy to successfully knocking him out using the very same technique Harry did during their first encounter.
It is implied that Michelle and her daughter left Dean to live with her son Eggsy after the brawl at the bar.
Dean is a foul-mouthed and cruel old man who not only violently inflicts abuse on his wife and step-son, but also believes no one is allowed to mess with him, which explains his behavior when attempting to find out who assaulted his gang in the pub. He is more than likely an alcoholic, which could be a contributing factor to his violent behavior. He was willing to murder Eggsy in order to find out who attacked his gang in the pub. It is also likely that he married Michelle for her first husband's money, hardly showing any romantic feelings for her.
Aside from his lack of familial love (especially for his daughter), he also shows little interest towards his gang due to being egotistical; even when his gang learned that Eggsy has become a skilled Kingsman and warned Dean not to mess with him, Dean angrily tells them to shut up, only to end up being knocked down by Eggsy himself.
- His friends
- Gary "Eggsy" Unwin - Stepson