All evidence suggests that Bob Odenkirk and David Cross are complex people. But they keep things charmingly simple in the self-explanatory documentary “Bob and David Climb Machu Picchu.”

“This is a movie about a trip I asked my friend Bob to take with me,” says Cross towards the start, and that really is the premise. If you’re intrigued by the idea of 80 minutes in the company of these two longtime collaborators, you’ll love hiking alongside them as they reminisce, laugh, and kvetch.

The image of two very funny men chasing a bucket-list item while bonding immediately brings to mind the summit of this particular genre: “The Trip” series, starring Steve Coogan and Rob Brydon.

This version is far looser, messier, and ultimately less impactful; the “Trip” films, which are lightly fictionalized, are visually stunning and deeply layered. But perhaps it’s not a fair comparison, since this project feels like an on-the-fly happenstance: the essential goal, one senses, was not to make a movie, but to capture a real experience for posterity. Director Michael LaHaie seems, more than anything, to be along for the ride.

And as a ride-along, it works. We learn more about both men, including that Odenkirk drifts dark, and seems to be the more demanding of the pair, both professionally and personally. Cross, in contrast, is his ideal foil: happy to both balance and make room for his old friend’s foibles.  We don’t even see a hint of annoyance every time he has to step quietly aside, as international tourists shout “Saul!” and want pictures of Odenkirk.

LaHaie also makes time to contextualize the duo’s friendship, by taking us back to their earliest years. They met on the set of the cultishly adored “Ben Stiller Show” in the early 1990s, and then co-created the even-more beloved sketch comedy series “Mr. Show with Bob and David.” Since then, of course, their careers have gone in different directions — Cross leaned into comedy, with “Arrested Development” and animation (among many other projects). Odenkirk, of course, went from “Breaking Bad” to “Better Call Saul” to the “Nobody” action movies.

But they still share a connection that only two people with common history and overlapping values can. Both appear devoted to their families, and also to each other. A sweetly easygoing Cross lifts Odenkirk’s spirits by teasing him like a little brother, and the thoughtfully solemn Odenkirk loyally (and accurately) reminds tourists focused on his fame that “Arrested Development” is one of the greatest shows of all time.

It’s also pretty poignant to see youthful footage of their early standup contrasted with their present realities. They’re in their early 60s, and in fact in the prime of their personal and professional lives. But Odenkirk’s 2021 heart attack hangs over their jokey, old-man banter and genuine physical challenges as the air gets thinner and the trail steeper. They also talk at length about their families, with deep love and respect.

Both men, and Odenkirk’s wife, Naomi, are producers on the film, and Naomi calls them “two unalikes, each making the other better.” We see just what she means, and ultimately “Bob and David Climb Machu Picchu” does feel like a warm and affectionate home movie. How fortunate for us that we get to join in on their big adventure.