Psych 2: Lassie Come Home quietly addressed Psych: The Movie’s cliffhanger ending instead of building on its clear setup. The first Psych movie teased a big new storyline centered around John Cena’s character. Prior to the first movie, Cena only made one appearance in the USA series, guest-starring in season 4 as Juliet’s brother, Ewan O’Hara, a highly respected soldier who performed top secret missions for the United States military.
At the end of Psych: The Movie, Ewan O’Hara returned for a last-minute cameo where he met with Shawn (James Roday Rodriguez) at Gus (Dulé Hill) at their new Psych office in San Francisco. At first, it appeared that he was there to congratulate Shawn and Juliet (Maggie Lawson) on their wedding, but it turned out that Ewan was actually on the run with armed men chasing after him. Shawn, Gus, and Ewan were all being shot at when the movie ended. The cliffhanger ending left an impression with viewers that this was the story Psych 2 would follow, but it was not so. Instead, Psych 2: Lassie Come Home centered on Shawn and Gus returning to Santa Barbara to investigate strange, possibly supernatural sightings around Lassiter (Timothy Omundson), who was severely injured in a mysterious shooting.
Since Psych 2: Lassie Come Home featured a big time skip, whatever happened with Shawn, Gus, and Ewan was over long before the sequel began. However, the movie did at least address their adventure with Ewan, albeit in an ambiguous way. In the scene at the Norwegian ice bar, Ova (Christopher Heyerdahl) asked Shawn and Gus if they had ever been to Norway. Shawn replied, “Just once. With my brother-in-law”, to which Gus replied, “We don’t talk about that, Shawn”. Since Shawn’s brother-in-line is Ewan O’Hara, this means that the three of them either fled to Norway to escape their pursuers, to investigate what was going on with Ewan, or were taken there by force. Either way, whatever transpired there was obviously something Gus had no interest in revisiting.
Psych 2: Lassie Come Home doesn’t provide a proper conclusion to the story with Ewan, but it did at least find a way to subtly acknowledge it. Since it’s in the past now, it’s unlikely to explore it much further in Psych 3 or a different sequel (though another John Cena cameo could be in the cards).
So why did Psych 2 abandon the first movie’s sequel tease? It’s hard to imagine the Ewan O’Hara story being compatible in any way with the events of Psych 2: Lassie Come Home. Psych creator Steve Franks and others involved have said in the past that though there were other stories they wanted to tell in Psych 2, the one they decided to go with was a Lassiter story. Timothy Omundson’s stroke inspired the writers to build a story around the actor’s medical situation, and it gave the main characters a good reason to return to Santa Barbara and the old Psych office.