This image released by Lionsgate shows Sylvester Stallone, left, and Arnold Schwarzenegger in a scene from "Expendables 3." (AP Photo/Lionsgate, Phil Bray)

“The Expendables 3” proves that when it comes to summer action movies, first and last impressions really matter. Both the explosive opening and the massive battle scene that caps the film offer some of the best full throttle fun of this summer’s offerings.

They are exciting enough to distract from a middle that sags under unnecessary dialogue, a travelogue to put together the next generation of Expendables and pages of silly banter. A 30-minute edit would have quickened the pace between the opening and closing and really given the production a lot more punch.

Just as in the previous two films, the ever snarling Barney Ross (Sylvester Stallone) leads a group of aging warriors on an impossible mission. The film starts with a prison break that brings Wesley Snipes to the team playing a knife-throwing killer named Doc.

Along with Christmas (Jason Statham), Gunner (Dolph Lundgren), Toll Road (Randy Couture), Caesar (Terry Crews) and the newly freed Doc, Ross goes on what he thinks is a routine mission. Everything goes bad when he realizes his target is Stonebanks (Mel Gibson), an original member of the Expendables that Ross thought he killed years ago when Stonebanks went rogue.

The failed mission in what ends up being no country for old men sends Ross on a quest to put together a younger team that includes a she-devil fighter (Ronda Rousey) and a smooth-talking motorcycle rider (Kellan Lutz). It’s putting this young team together that turns a fast-paced action movie into a painfully dull road trip.

Things get worse when Gibson’s character finally gets to speak. His endless speeches drone on to the point of nearly perfect dullness. Stallone and fellow screenwriters Creighton Rothenberger and Katrin Benedikt should know after two movies in this franchise the main thing to remember is: action good, dialogue bad.

Much of the dialogue features the one liners that all of these action stars have used along the way.

The joke by Snipes about being in prison for tax evasion and Arnold Schwarzenegger’s growling command to “get to the chopper” are good for some giggles. Mostly, the writing borders on mimicking a celebrity roast.

One saving grace is the addition of Antonio Banderas to the mix. His rapid fire chatter and manic actions are like a three year old who’s been given a box of sugar soaked in a soft drink poured over ice cream to eat just before bed. Banderas is one of the few actors who can play such an irritating character and still come across as likable.

“The Expendables 3” starts and ends strong. The middle just ends up being too much of a senior moment.

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