As far as casting goes, Elijah Wood seems like just the kind of guy to hallucinate a misanthropist talking dog. With his giant, frightened Precious Moments eyes and dapper type-A neatness, Wood's protagonist Ryan already seems to be at the brink of sanity when the pilot begins: here is Ryan typing up the fourth draft of his suicide note, here is Ryan blending his anti-anxiety meeds into a smoothie, here he is jumping rope in an effort to kill time before he dies. Here is Ryan meeting his psychological problems disguised in a dog costume.
Unfortunately for our protagonist's plan-making skills, Ryan wakes up the next day safe and sound…and the last-minute babysitter for Wilfred (Jason Gann), pet of beautiful next door neighbor Jenna (Fiona Gubelmann). When Wilfred starts smoking out of a Gatorade bottle bong and questioning Ryan's manhood, Ryan assumes he must be suffering the aftereffects of his death smoothie. When OB-GYN sister Kristen (Dorian Brown) reveals that the pills in his possession were in fact placebos, Ryan must slowly start to make sense of the hulking, wise-talking man-dog that everyone else on the planet sees as a regular pooch.
This new turn of events is simply the latest in a series of recent obstacles for Ryan. From what we can tell he lost his lawyer job, completely depends on his family for emotional support, and is slowly succumbing to the banal despair of the everyday grind. Meanwhile, Wilfred makes himself at home, digging holes in Ryan's immaculate backyard, demanding a walk, begging for him to throw a tennis ball. The two spend a meandering day getting to know one another, as Wilfred gives a stunned Ryan particularly salient life advice (i.e. don't go into your first day of work, possum guts taste amazing, they just do). The two fit together well, in large part because it seems pretty clear Ryan isn't interesting in getting help from the humans in his life. His estrangement and deep loneliness is why his relationship with what even he knows is his delusion is believable. Wood's anxious energy and Gann's laid-back antagonism compliment each other well; they play like The Odd Couple for the deeply disturbed.
At the end of the episode, Ryan eventually stands up to Kristen and blows off the new hospital job she bent over backwards to land him, a scene that is, in his mind, proof of his new found life-force. Kristen is depicted as a snarling control freak, and Ryan's outburst a small triumph of the will, one tiny man's stand against the suffocating constraints of modern life. So it's only fitting that the last shot of the episode we see Wilfred's furry hand planting Ryan's wallet under the broken window of his big, psychotic neighbor's house. Wilfred isn't Ryan's supernatural life coach. He is his id as a talking pet. It only makes sense that Ryan's destructiveness isn't going to go away now that it's channeled through, or at least egged on by, a leg-humping, seemingly malevolent dog-person. In letting Wilfred be more than just an invisible buddy, the series asks the more important question, not "Why is there a talking dog?," but "What kind of person listens to a talking dog anyway?"