Tatum stars as Jackson Briggs, a US Army Ranger who was injured in combat and now suffers from the lingering effects of a concussion as well as PTSD. Despite this, he is desperate to return to active duty but is deemed unfit due to his injuries. Briggs gets word that a former army buddy of his- Riley Rodriguez- has died in a car accident: he wrapped his vehicle around a tree while DUI. A bunch of the Rangers gather at a bar to remember Rodriguez and Briggs takes the opportunity to ask his former commanding officer for the recommendation he needs to return to the service. His C.O. agrees to give it to him on one condition: Briggs takes Lulu, the military dog Rodriguez was the handler for, to Arizona; Riley's mother has requested her to be present at the funeral. This is a problem because Lulu, traumatized by her war service (during which she was shot) has become unpredictable and aggressive. She must be driven, because air travel now makes her freak out, and kept muzzled when around people. Briggs is reluctant to undertake the trip but does so because he's desperate for the referral. Before he leaves, his C.O. tells him that, after the funeral, he's to take Lulu to a nearby military base where she will be euthanized. Briggs packs an uncooperative Lulu- who tries to take a piece out of him- in a travel crate in his truck and heads out... and now we have a road trip movie.
The name of the movie doesn't do it any favours... really, that was the best their writers could come up with? And the film is rather uneven in places, because it doesn't quite know what it wants to be. It's billed on Amazon Prime as a comedy, and there are comedic elements in it- generally the most cliched ones. Will Lulu destroy the truck seats while left unattended? Will she at some point escape and cause disaster? Will the truck break down? Yes, of course, is the answer to all these questions. There's also a -supposedly- comedic scene in the movie which involves him trying to pick up girls in a bar in uber-lefty Portland, Oregon. While this might have been mildly amusing, it drags on for too long and never quite lands. Yeah, we get it... Portlanders are a bunch of hippie-dippy weirdos. And a little of them goes a long way; the movie wastes 'way too much time here instead of spending it where it was more warranted, like Brigg's attempt to visit his estranged wife and three year old daughter.
I won't spoil the ending of the movie, but it's safe to assume that after having Lulu endear herself to the audience all along the road to Arizona, it's not going to end with her getting a lethal injection in the back of the neck. Is the ending a bit predictable? Yes, but it's also well done and moving. Likewise the funeral scene... am I aware that having Lulu go and lie down on the grave of her former handler, with her head on his empty boots, while The Last Post is being played is deliberately manipulating me to tear up? Of course, but this doesn't make the scene any less effective or sincere. And Dog is at its best when it is being sincere; the comedy bits always seem a bit tone deaf and try hard.
So to sum up, I enjoyed watching Dog; it has its faults and is somewhat uneven, but these flaws are outweighed by its good points, of which there are many. And Lulu is very cute, to boot.