It's set in the future sometime where there's been a solar flare which has scorched the earth, exposed everything to radiation and those who survive are living in a lawless, featureless, barren landscape everyone fighting to stay out of the sun and find leftover food from before the event.
I say 'everyone' but actually, we don't see much of any other humans except for Hanks. He's some kind of scientist who can turn his hand to anything technical and has set himself up in his high-tech workplace where he's made a kind of trolley-robot and now, a big, strong, walking robot to be even more useful.
Turns out that the reason he's done this is to get the robot (who calls himself Jeff) to look after his little dog, who makes up the cast of four, should Hanks (Finch) die. Cast of four, loosely. Or three, two or one, however you look at it! The payroll is not spread thinly, shall we say! A dog trainer, Hanks and Caleb Landry Jones voicing Jeff!
There's some kind of event approaching and they have to get out of where they are or they will be buried forever, so they head for San Francisco where it seems that things might be a bit better - and not overrun with evil-minded other humans. At this point it turns into something of a Road Movie as they bump into problems and have adventures, largely brought about by the moronic robot's stupidity!
And herein lies the issue really. The robot, Jeff, is cast as more of a naughty and naïve teenager than a high-tech marvel. It's far too stupidly human in everything it does - and this is where the film turns very much into a 'Disney' for kids rather than an interesting concept to get one's teeth into. And the more rope they give the robot, the more soppy and sentimental it gets, ending with a series of outcomes which as-yet undiscovered tribes in Outer Mongolia would have seen coming!
There's much to pour scorn over here, unless you take it for what it is. A twee family film for all ages so everyone can say 'ooooh' and 'ahhhh' in the right places, then shed a tear or two at the end. Having said that, the CGI is very good. Jeff is made to move in very much a human way and so forth. The cinematography is great with loads of interesting visuals to feast the eyes on as well, so all is not lost.
It's just a bit of a non-event really. Small cast, not much of a story, slow and as dull as dishwater. It was close to not quite making it into Flop of the Fortnight, but it just gets there! Sorry Tom. We love you usually.