With an ominous new threat on the horizon, The Avengers must reunite to prevent the Mad Titan Thanos from collecting six magical infinity stones that will grant him almost unimaginable power.

When Marvel Studios launched their ambitious cinematic universe with 2008's Iron Man, few would have thought that 10 years on the franchise would still be going strong. Yet 17 popular films later, expectation has built to fever pitch levels for this third team-up film. This time it unites not only the Avengers, but other Marvel characters such as Spider-Man, Black Panther and the Guardians of the Galaxy.

Robert Downey Junior returns to reprise his role as Tony Stark and is joined by a huge ensemble cast including Chris Evans, Scarlet Johansson, Chadewick Boseman and Mark Ruffalo.

Faced with the daunting task of arranging so many characters into a coherent story, directors Joe and Anthony Russo only partly succeed.

The action heavy script is rather thin on plot and sees Josh Brolin's Thanos methodically targeting the splintered heroes in search of the mystical stones.

The result is a series of hectic battles that span the entire universe.

Fans who have invested their time in the franchise will enjoy the many links to previous instalments, however it will may leave newcomers bewildered.

The fact that a sequel is planned for next year is also quite apparent as events lean heavily towards set-up.

The film's real joy comes from seeing this vast array of superheroes interact.

The bickering caused by the clashing egos of Downey Junior's Iron Man and Benedict Cumberbatch's Doctor Strange is amusing, while the interplay between Chris Hemsworth's Thor and the charismatic Chris Pratt as Starlord is a real highlight. The problem is that with a cast this big, it is almost impossible to give anybody significant screen time and these great moments are too fleeting.

Nevertheless, the film moves at an astounding pace and has so much happening that it is easy to get swept along. Even with its mammoth running time of two and a half hours, it is never boring and fans of the recent Black Panther film won't be surprised to hear that a wonderful third act battle in the African country of Wakanda is the film's finest moment.

With such elevated levels of expectation, the Russos were never going to please everybody and while they haven't produced the masterpiece fans would have hoped for, Infinity War is an admirable effort.

An epic but overstuffed spectacle with enough memorable moments to have fans queuing up for the next instalment.