At one point late in “The Expendables 2,” Sylvester Stallone, Bruce Willis and Arnold Schwarzenegger stand shoulder to shoulder in the same frame, using enormous machine guns to blast away at some bad guys. The sight of the three huge stars in the same movie doing something other than talking (which is all they did in the previous film) should be funny and exciting and nostalgic all at the same time – a kind of wish-fulfillment fantasy for action-movie fans.

Instead, all you notice is how Schwarzenegger, whose stint in politics has left him with a bit of a paunch, winces when he fires his weapon, as if he were a little afraid of it. Or how Stallone’s face has been pulled and stretched to the point that it is almost grotesque. Or how utterly unengaged Willis looks, as if he were wondering how much longer he needs to hang around before his scenes are done and he can go cash his paycheck.

Released in 2010, “The Expendables” grossed nearly $300 million worldwide. A sequel was inevitable, especially since the project was Stallone’s baby, and he hasn’t been working much lately, so what else is he going to do?

Stallone co-wrote “The Expendables 2” with Richard Wenk (“The Mechanic,” “16 Blocks“) and he wisely handed over the directorial reins to Simon West (”Con Air,“ “Lara Croft: Tomb Raider”), who knows how to orchestrate enormous action set-pieces. West throws in everything he can think of – car chases, boat chases, foot chases, jet-ski chases – but he doesn’t cut it together well, so the action becomes abstract: It’s all explosions and guns and crashes and unnaturally loud punches.

There are loads of horrendous one-liners (“Rest in pieces!”), lame attempts at meta-humor (Schwarzenegger: “I’ll be back.” Willis: “You’ve been back enough. I’ll be back!“) and brief, horrifying glimpses at plastic surgery gone wrong. Rumor is a third “Expendables” movie is in the works, with Steven Seagal, Harrison Ford and Nicolas Cage potentially joining the cast. I’d rather see a movie where all these actors sit around playing poker and joshing each other than have to sit through another shoot-em-up for septuagenarians.