"There’s zero plot really in that movie anyway, you could do anything and call it a sequel," the actress joked. "Anything [at all] and just have that group of people… [and] I would do it in a heartbeat."
In the 2008 farcical comedy, Hahn plays Alice Huff -- wife of Adam Scott's character, Derek Huff, and sister-in-law to Ferrell's Brennan Huff -- who begins a wild, off-kilter romantic affair with Reilly's Dale Doback.
Directed by Adam McKay -- who previously brought Ferrell and Reilly together for the 2006 NASCAR comedy Talladega Nights: The Ballad of Ricky Bobby -- the film featured elements of heavy improv from its entire cast, which was a relatively new experience for Hahn, at the time.
"That kind of broke it open for me as a performer, working with those guys," Hahn recalled. "I mean that was a real anarchic moment for me. I was like, 'You can do this on camera?'"
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The star explained that shooting that film, with that cast, was a "turning point" for her as an actress.
"I didn’t know you could improvise like that. I didn’t that you could be that lawless. I didn’t know you could throw the script away like that," she shared. "It was the best."
As for where she could see the characters in a possible sequel, Hahn said it would "have to be something to do with Catalina, because I think it’s such an iconic part of that movie," referring to the film's hilarious comedic crescendo at the Catalina Wine Mixer.
"[And] I feel Alice is in jail somewhere," she added, referring to her own over-the-top character.
In Hotel Transylvania 3: Summer Vacation, Hahn stars as Ericka Van Helsing, the captain of a luxury cruise liner who is also the descendent of famed vampire hunter Abraham Van Helsing. When a Dracula (Adam Sandler) falls for her during his family vacation, she secretly plots his demise. The animated sequel -- also starring Selena Gomez and Andy Samberg -- hits theaters July 13.