(This post has no significant spoilers for "Mad Dogs," even though it's informed by a viewing of the entire first season. The comments section is a place where it's okay to discuss the full plot if you've finished it, but I'll be doing a separate post on Monday touching on a few developments from later in the season.)

Late in the first episode of Amazon's newest original series "Mad Dogs," the show's four main characters — played by Romany Malco, Michael Imperioli, Steve Zahn, and Ben Chaplin — witness an act of violence. By the standards of modern TV drama, what they see isn't particularly extreme. But they're not watching it on TV, nor are they the sorts of jaded tough guys who populate the shows where this kind of thing might happen. They're just ordinary middle-aged guys on a vacation gone tragically awry, and as they consider the blood in front of them, they are clearly terrified by what they've just witnessed, and by the possibilities of what could happen next. The "Mad Dogs" premiere takes its time with this scene, lingering over the stunned faces and trembling bodies of all four men, so that we can fully appreciate how out of their depth they are.

By the end of the 10-episode first season (which Amazon premiered in full last night), they haven't exactly gotten better at dealing with men pointing guns at them — their frequent ineptitude in high-stakes situations dominates a show that's as much a black comedy as it is a thriller — but they've definitely grown accustomed to life-and-death peril, to the point where they can even joke about it a little.

"People have been really nice," Imperioli's Lex observes at one point.

"Really nice," admits Malco's Gus. "Apart from the ones trying to kill us."

That shift in response is all but inevitable in a story like this, where the four former college buddies endure one nightmare after another in their attempt to get out of Belize alive. But it also speaks to the difficulty of sustaining a show — even over a relatively brief first season, never mind over the potential multiple seasons it could run — with such a seemingly limited premise as The Worst Holiday Ever.

Adapted by Cris Cole from his British series of the same name — where Chaplin played the fifth friend (a role filled in the remake by Billy Zane), now a wealthy Belize businessman, who brings them together for this ill-conceived reunion — and produced by Shawn Ryan ("The Shield," "Terriers"), "Mad Dogs" prompts contradictory reactions. In almost every moment, it's both compelling and eyeroll-inducing. It's a show where the same awful thing just happens again and again, varying only in the details of who gets hurt and what type of stupidity our heroes display. But that still works from moment to moment because the four leads are so incredibly watchable, and have been given just enough to play beyond their present circumstances so that each man feels like a real character and not a plot functionary.

Over the course of these 10 episodes, the guys run afoul of drug lords, dirty cops, CIA operatives, and a little person assassin fond of wearing a stylized cat mask, among other problems, and they have an uncanny knack for making the worst decision in every circumstance. (Does Murphy's Law apply if so much of what's going wrong is your own fault?) As a result, "Mad Dogs" can be a stressful experience — or a cathartic one, if you're apt to yell advice at fictional characters who very badly need it — and perhaps not ideally suited to the binge-viewing model Amazon favors. For that matter, the repetitive nature of the guys' dilemma — it's essentially "Gilligan's Island" as serialized cable drama — becomes even harder to ignore when watched all in a row. The original "Mad Dogs" had shorts seasons even by UK standards — four episodes apiece for the first three seasons, then only two for the final one — and though I don't know how much Cole, Ryan, and company are deviating from the original plot, there are certain settings and characters who feel like they're introduced entirely to kill time before returning to the original path. (There's an episode where the guys end up in quarantine, because of course they do. It's not the show's finest hour, and dwells more than most on them using this crazy experience as an excuse to settle old beefs with one another.)

Yet for all this, it's never boring. The four leads have terrific chemistry, and play the roles with energy that belie their characters' suburban complacency. And the show continually throws interesting guest actors at them, including Allison Tolman ("Fargo"), Ted Levine ("Monk"), and Coby Bell ("Burn Notice"). (Sutton Foster has a cameo at one point for which she seems strangely overqualified until you remember that she's married to Ryan's old "Terriers" partner Ted Griffin, who directed one of the later episodes.)

With Belize (played in the show by Puerto Rico, which is much closer for production purposes, while still offering lots of interesting locations to shoot), "Mad Dogs" threads the needle between exoticism and condescension. This is a confusing place these guys have to navigate, yet the locals they meet (most notably Rachael Holmes as an innocent pharmacist who keeps getting pulled into their mess) come across as people with their own problems, rather than caricatured obstacles.

When Amazon first showed its customers the "Mad Dogs" premiere a year ago as part of its vaguely crowdsourced pilot process, I was impressed, but had to admit to Ryan that I had no idea what the series would be long-term. Nine episodes later, I still don't. The season achieves enough closure that, were Amazon to decline to order more, this would be a satisfying narrative experience, but it also leaves just enough open that one could imagine the guys going through some variation of this ordeal yet again. It seems to make much more sense as a shorter story, whether as an American miniseries or following the structure of the original.

Ryan's been to this particular dance before, though. Go back and watch the pilot of "The Shield." Great as that is, could any of us have imagined that show — which also had a shocking piece of violence at the center of its first episode, and whose main character seemed to be perpetually digging himself out of the same kind of narrative quicksand in which the "Mad Dogs" men find themselves — would run for 88 episodes over seven seasons, with only occasional (and very brief) dips in quality, and that it would end with perhaps the greatest TV finale ever?

I'm not saying that "Mad Dogs" will be the next "Shield," just that I trust Ryan to keep all these plates spinning far more than I would almost any other producer in the business. And every time I was on the verge of throwing up my hands at the seemingly limited structure, "Mad Dogs" would present some haunting image I wanted to see more of, or one of the actors (usually Malco or Zahn) would have the perfect reaction to the latest bad turn of their story, and I would realize how much I wanted to know what happened next, even if it was likely to be the same damn thing that had happened six times before. 

Alan Sepinwall may be reached at sepinwall@hitfix.com

Alan Sepinwall has been reviewing television since the mid-'90s, first for Tony Soprano's hometown paper, The Star-Ledger, and now for HitFix. His new book, "TV (The Book)" about the 100 greatest shows of all time, is available now. He can be reached at sepinwall@hitfix.com