|First appearance||"The Impertinence of Being Honest"|
|Last appearance||"Bon Voyage"|
|The Deep End|
|First appearance||"New Year's Dissolutions"|
|Last appearance||"Golden Opportunity"|
Denny's first appearance in the series is in Season 6, when he helps Giles Kane track down his biological father. Denny returns not long after and decides to settle down in Bloomer, operating a detective agency out of a room in the Shady Glades retirement community. Denny becomes a main character in Season 7, and begins pursuing a new dream; writing detective novels, which are then adapted for WKZT. However, he decides to focus on his agency full-time prior to the start of Season 8. A year later in Season 9, a routine check-up at the dentist introduces Denny to the love of his life; Becky Simpson. They marry early in Season 10, and have their first child together in that season's finale. Denny and Becky soon realise how much they love having kids and end up bringing four more into the world in the following seasons. Towards the end of Season 15, Denny is offered a job with the CIA thanks to his keen observation skills, and departs for L.A. with Becky and the kids. Denny briefly appears in the series finale, sharing a goodbye with Roz via webcam.
The Deep End
After the conclusion of Vintage Roz, Denny's devotion to his new job results in increased feelings of distance from Becky, leading to their separation and eventual divorce. A downtrodden Denny shows up on Adelaide Park midway through Season 11, hoping to kick-start his investigative career after losing his job with the CIA. Silas Nolan allows Denny to re-establish his detective agency on the business park, which is a moderate success until the park is shut down at the start of Season 12. Denny develops a close friendship with Chloe Nolan while helping her launch the Top Banana, which almost blooms into a full-fledged relationship until Chloe discovers she is pregnant with Felix Delgado's child. After spending the following year and a half feeling forlorn, Denny runs into Becky and contemplates starting things up with her again, only to find she has returned to Bloomer. In the series finale, Denny bestows a gift to Pam Gates to ease the Top Banana's financial concerns, and leaves for Bloomer on a whim to reunite with Becky.