When the stakes were at their very highest, the Avengers failed. Thanos collected the Infinity Stones, clicked his fingers and annihilated half of the life in the universe. Five years later, a rat and a freshly-released Ant Man offer a new hope, a lifeline that could turn defeat into victory and save half the known universe. The only catches are that it requires inventing a whole new science and gatecrashing significant periods from their past to claim the infinity stones and bring them to the present to reverse the deadly click. There is only one chance, no do-overs and a very good chance that they will not all be coming back. Then again, if it was easy it wouldn't need the Avengers.

AVENGERS:INFINITY WAR brought all of the disparate plotlines of the many Marvel Cinematic Universe characters together in a dramatic climax that would have been audacious in its shocking twist at the end, except that the audience knew there was still one film left for that outrageous ending to be put right. The outcome has never really been any doubt, but the question is how the saga gets its faithful viewers to that point and provide a predictable outcome that manages to be exciting and satisfying. That's a very, very big ask.

It makes us happy, then, to announce that the writers and directors have pulled off the near-impossible for the second film running (we're not counting the two prequels released between AVENGERS:INFINITY WAR and AVENGERS:ENDGAME). Faithful audiences who have followed the sereies since the very first IRON MAN back in 2008 will have no complaints as they leave the cinema. Upon later reflection, there will be questions to be asked, but that's for later.

Though the running time is a mammoth 3 hours, but it doesn't feel anything like that such is the amount of story that has to be jammed into that running time. That said, the importance of the characters is never allowed to be overshadowed by any of the spectacular action. And the action is spectacular, climaxing in a ridiculously huge battle involving every surviving member of the MCU. The stuntwork and CGI combine seamlessly to provide a battle sequence to rival those from THE LORD OF THE RINGS. There are plenty of smaller fights along the way.

Surprisingly, though, the film spends at least as much time on the character work as it does on the action stuff. Before the plan to save the day even goes into action, we see all the remaining heroes struggling with the immensity of their loss. Steve Rogers leads a survivors' support group, exhorting the others to move forward when he is unable to do the same. Natasha continues to run the Avengers, tackling the smaller problems with a determination born out of it being the only thing that keeps the despair at bay. Barton hunts down the gangsters he deems unworthy of surviving the blip (as it has come to be called). Even when a surprising source brings the possibility of a solution, a redemption, there are those who struggle with what taking it will mean for their current lives. Finally, the decision is made and the time heist is one.

Yes, it can hardly be a surprise that time travel is going to be the get out of jail card for the writers. Having painted themselves into the corner of Thanos winning, only a big reset button can save them and that reset button is called time travel. It's a hoary old idea (see how many times it's been used in shows like DOCTOR WHO), but the execution is delightful. In order to gain access to the stones, they must travel back in time to the events of other films, without upsetting the events already in place. Thus we get to revisit the battle in New York from MARVEL'S AVENGERS ASSEMBLE, the opening sequence of GUARDIANS OF THE GALAXY and the Asgard of THOR:THE DARK WORLD. The familiarity alongside the new developments works beautifully, throughout.

And whilst the storyline is serving up a healthy helping of nostalgia and action, the script serves up plenty of clever banter alongside the more sombre moments. Everyone gets a bunch of great lines and they all come directly from their characters, continuously underscoring the humanity of the situations. Whether it's Tony Stark getting to spend some quality time with his father, Banner embarrassed by the actions of the earlier era Hulk or Thor's desperation to bring himself back from the drunkard he has become, there is enough heart in all of these moments to keep accusations of empty spectacle at bay.

And then there are the events on Vormir, that serve to underscore the fact that this may be a fun jaunt, but it's a fun jaunt with very real consequences for the characters involved.

It's fair to say that the time travel mcguffin doesn't really add up, the rules never quite being followed and cause and effect being bent to serve the purposes of the plot, but there is enough momentum at all times to make sure that's not really a concern until the audience is out in the clear light of day and thinking about it more clearly. There are also some issues with Thanos's plan which don't quite add up, but again those can be ignored until after the fact.

And then there are the events on Vormir, that serve to underscore the fact that this may be a fun jaunt, but it's a fun jaunt with very real consequences for the characters involved. Not everyone is getting out of this alive and for an audience that has come along on this journey, some moments may bring them to tears. It's been a wild ride, but this is a very fine send off to Earth's mightiest heroes.