I would imagine that most people have seen at least an episode of Zach Galifianakis' comedy shorts entitled "Between Two Ferns" where he invites big stars onto his show, pretends to not know who they are and simply makes fun of them. He has managed to pull in the biggest names on these shorts and they are almost always hilarious.
The movie takes it a bit further
In the film, much like the shorts, Zach pretends to be a local public-access tv-show host that is not famous but somehow manages to have access to the biggest stars in music, television, and movies. He uses 1980's computer graphics and routinely spells their names wrong such as "Brad - Lee Cooper" or "Jerry Signfeld." He is normally very mean to his guests and the best part about this is that the guests, who are obviously friends with Zach in real life, don't get prior knowledge of the questions but need to remain in character.
Sometimes the guests, knowing that Zach is going to be mean to them, come armed with their own insults and everything is ad-libbed from that point forward.
These are the shorts on Funny or Die's website and the film centers mostly on doing exactly that but brings in a story that involves an adventure with the crew of "Between Two Ferns" needing to travel across the country, interviewing celebrities along the way
They encounter various problematic situations along the way such as running out of money and the fact that they don't particularly care for one another. Zach also lets the ferns ride in the front seat while all of his crew has to squeeze into the back.
The problem I have with the story is that it isn't very entertaining. The truly entertaining and funny aspects of this movie are the interviews of the celebrities and the situations that occur in the middle all seem kind of trivial. I understand that in order to have a full-length feature that this was necessary but I found myself skipping a lot of it because i got bored.
From the Netflix official channel
I laughed a lot during this movie, but almost exclusively during the interviews. I hate to be a Debbie Downer but the bits that take place in-between generally aren't very funny and this is where I started messing with my phone and eventually picked up the PS4 controller to scroll through to the next interview - because those are great.
Overall, i would say you should watch this, especially if you appreciate the Funny or Die shorts. The story between the interviews isn't terribly necessary, nor do they really have anything to do with the overall plot. Zach's deadpan delivery of the most awful questions to some of the most famous people in the world is reason enough to see it.