Not even superpowers can defeat the law of diminishing returns in this insufferably smug comic book action sequel.

Ryan Reynolds indulges his taste for lavish attention seeking and mawkish self pity in his return as the mutant mercenary turned hero, Deadpool.

He creates the X-Force, a team of super-powered people and an alternative to the X-Men, some of who appear here.

X-Force’s mission is to save a fire-starting mutant orphan from being killed by a soldier from the future, called Cable, played by the meaty Josh Brolin.

If the deal for 20th Century Fox to be bought by Disney goes through, Deadpool may soon feature in the Marvel cinematic universe alongside Iron Man and the rest. Which may be problematic as over there Brolin plays the super villain, Thanos.

An X-Force parachute drop is easily the most entertaining sequence but the rest of the film is a slog, being a dull vehicle for Reynolds to banter his way through a series of fights, car crashes and explosions. The sex scenes of the first have been replaced with yet more shoot-em-ups.

Many of the original supporting cast return, bolstered by the winning presence of Zazie Beetz as Domino, a hero with the ability to manipulate luck.

The first Deadpool film was characterised by a bullying sensibility and child abuse jokes. It so successfully pandered to the worst instincts of its target audience of 15 year-old boys, it made over ten times its budget and became the highest grossing X-Men movie.

With a bigger budget, the CGI is more expensive and the jokes are cheaper. Reynolds co-wrote and it’s less than 2 minutes before the first paedophile joke arrives. Most of the rest of the gags mock other superheroes and frequently fall flat.

I wasn’t a fan of the first Deadpool adventure and I enjoyed this one even less.