Let's not beat around the bush - The War with Grandpa is bad.
The film, which was apparently completed in 2017 but only just released this month, passes itself off as a family comedy, but it's just cringe-worthy for the majority of the run-time.
And, incomprehensibly, it features a really stacked cast including three Oscar nominees.
Robert De Niro (Oscar nominee number one) plays Ed, the titular Grandpa, who is at war with grandson Peter (Oakes Fegley, Pete's Dragon) over a bedroom.
The kid feels hard done by because mum Sally (Uma Thurman, Oscar nominee number two) moves Ed not just into the house, but into Peter's room, forcing the youngster to take up residence in the attic.
Egged on by his school buddies, Peter decides to declare war on his Grandpa, escalating pranks to ridiculous proportions. The senior is content to let it slide until he too is egged on by his buddies, man-child Jerry (Christopher Walken, Oscar nominee number three) and Danny (Cheech Marin).
The ridiculous 'acts of warfare' range from rigging marbles to spill all over the floor to putting a snake in a bed - and everything in between.
It's almost embarrassing to watch such fine actors - Jane Seymour and Rob Riggle also star - taking part in such a terrible movie.
The slapstick is truly awful, most of the jokes are not even slightly funny and there is so little believability factor that it's pretty impossible to care about any of the characters.
The one shining light is an actually hilarious scene involving an inappropriate ringtone at a funeral.
But one funny scene does not a funny movie make.
If you've got any inclination to stick around after the lights come back on, you'll find the most mind-bogglingly redundant gag reel ever. There are no funny moments, just random outtakes that seem to have no purpose, and shots of Laura Marano (who plays Peter's sister) singing into a microphone, but not along to the song that's actually player through the sequence.
It's very confusing.
