Thor: The Dark World is due to be released in the US this weekend. The sequel to the 2011 Marvel film sees Thor (Chris Hemsworth) reuniting with Jane Foster (Natalie Portman) in order to face a new and dangerous enemy.

Tom Hiddleston
Tom Hiddleston's performance as Loki has been highly praised.

Critics have been largely underwhelmed by the film and have described it as lacking in the vigour and excitement of its predecessor. Critics have commented on two particular, and crucial, aspects of the film: namely the "overcomplicated" plot and the "tacky 3D effects."

Michael O'Sullivan of the Washington Post felt the film was "slow to get going and features too many undeveloped threads." In a similar vein, The New York Times critic, Jeanette Catsoulis, thought the dialogue was "lumpy" and the plot "leaden." The latter word was also used by USA Today's critic Claudia Puig. 

Chris Hemsworth as Thor with Anthony Hopkins as Odin.

Tom Hiddleston who plays Loki, Thor's mischievous brother, has been highly praised by critics. This could arguable be because his character presents a good deal more complexity than the clear cut traits of Thor. He, according to the New York Times critic, "Moves his fine-boned features and graceful body, as if what he were doing matters; he seems imported from a quite different movie." This is echoed by Peter Travers, of Rolling Stone magazine, who stated there was "not enough Loki."

Watch the movie trailer for Thor: The Dark World:

Overall, it is not the acting which lets the film down as Michael Phillips (Chicago Tribune) writes "Plenty of fine actors do what they can here amid the digital mayhem and smashed columns." It is, unfortunately the special effects, an element which is of paramount important in superhero films, but has failed in Thor: The Dark World to hit the mark.

Where critics have positively reviewed the film, other than the quality of the cast, they have commented on the comedic aspects of the dialogue and the enjoyment of watching a relatively standard superhero film. In fact, despite negative reviews overseas, the film has been highly successful worldwide.

Contactmusic's critic, Rich Cline, has positively reviewed the film, noting a few issues other commentators also picked up on. Cline described the film as "entertaining" and gradually becoming "crazier" as the plot unravels.

Read Rich Cline's review of Thor: The Dark World on Contactmusic.

Thor: The Dark World is out in UK and Australian cinemas now; it is released in the US on Friday 8 November.

Natalie Portman and Chris Hemsworth star in Thor: The Dark World.