One of the pleasures of “American Made,” the new Tom Cruise movie, is watching an average American — well, an average American scam artist — tying several muscular arms of the U.S. government in knots. It’s hard to say how faithful the movie is to the facts of this real-life case (director Doug Liman calls the film “a fun lie based on a true story”), but you have to take your Schadenfreude where you can get it, and here it is.

Having weathered the charisma hit of “The Mummy” less than four months ago, Cruise is back at full star wattage here, completely engaged and funnier than he’s been in years. He’s playing Barry Seal, an airline pilot back around the turn of the 1980s. Barry has an illicit sideline — smuggling Cuban cigars in from South American runs — that has brought him to the attention of the authorities. Although not the authorities he might have expected.

Seal is approached in a bar one night by a smirky character named Schafer (Domhnall Gleeson), who knows all about his small-time cigar scam and proposes to repurpose Seal’s criminal inclinations for the benefit of Schafer’s company — which turns out to be the CIA. It seems the agency also has an interest in South America (“We’re building nations” down there, Schafer says), and it wants Seal to start flying photo-surveillance runs to document all the Soviet-backed commies infesting the subcontinent and stirring up trouble in places like Guatemala, Honduras, El Salvador. This sounds like spying to Seal — can it be legal? “If you’re doin’ it for the good guys…” Schafer says.

Things get out of hand pretty quickly. Seal soon finds himself playing bagman for CIA client Manuel Noriega (Alberto Ospino), the Panamanian dictator, who’s helping to funnel agency money and arms to Nicaragua’s right-wing Contras, who are battling the country’s left-wing Sandinista government, which the CIA dislikes a lot. Then, when Seal touches down in Colombia one day, he is greeted by members of the Medellin drug cartel, among them Jorge Ochoa (Alejandro Edda) and Pablo Escobar (Mauricio Mejia). The narcotraficantes know all about Seal’s weekly CIA surveillance flights, and they want him to start taking serious quantities of cocaine back home with him on return trips. Seal agrees to this because (a) these guys will kill him if he doesn’t, and (b) he’ll be making unreal amounts of money.

The plan works out well. Seal starts dropping bundles of coke down to pickup teams in his home state of Louisiana and air-traffic controllers pay no mind because his plane is flagged as CIA aircraft. Then the agency moves Seal and his wife, Lucy (Sarah Wright), and their kids to tiny Mena, Arkansas, where it has built him a new house and a whole airport — a very private base for a new assignment: flying crates of CIA-provided AK-47s directly to the Nicaraguan Contras. Eventually, everyone sort of throws their hands up and decides the coke should go to the Contras and the AK-47s to the Medellin drug lords. Problems solved!

The story grows ever more complicated, and several timeline switchbacks tend to thicken the narrative murk. But Cruise is funny throughout. His Barry Seal is a sharp, adventurous guy who can’t believe his luck (when he has it) and can’t help but laugh at the absurd situations in which he becomes enmired. Although he winds up bringing home so much ill-gotten loot that he can’t dig holes fast enough to hide it in, his main concern is always his family. (The movie heavily references “Goodfellas,” and so his wife Lucy, a blue-collar beauty, easily becomes addicted to the closets full of cash that furnish their new filthy-rich lifestyle.)

The picture probably benefits from the fact that both Cruise and director Liman are pilots themselves — the flight scenes have a loose, breezy spirit. And Cruise is well-supported by Gleeson — a study in cheery bureaucratic amorality — and by Jesse Plemons (as a clueless sheriff) and Caleb Landry Jones (great once again as Lucy’s dim-bulb brother).

As star vehicles go, “American Made” is refreshingly unassuming. The movie has a nice, low-key amiability, and it finally puts Tom Cruise back in synch with his talent.