A film critic's urging Marvel fans to ignore the reviews from people like him, before heading into the marathon finale of the Avengers franchise.

Endgame wraps up the mammoth 22 film series, which is the highest grossing movie franchise of all time.

Flicks editor Steve Newall told Mike Yardley he went to an advance screening.

"Hype was a little bit light on this one as the first reactions did not come out until yesterday afternoon. I'd encourage anyone to not listen to what I have to say or anyone else, and just come to this thing cold."

However, he promises that fans can expect a "real ride".

The movie comes in at slightly over three hours, a rarity in modern blockbusters, but Newall says that there is no good time to take a bathroom break. 

"It rolls right through. They find a way to make this movie a victory lap and simultaneously a nostalgia trip for what we've been watching for the last 10 years."

He says that promotional material has only revealed about 15 minutes of that massive runtime, and there are plenty of surprises in store for expectant fans.