It’s hard to imagine a film director more different from the self-serious Oliver Stone than the often comedic and deeply self-aware Adam McKay. But as I watched McKay’s “Vice,” it reminded me of Stone’s “W,” and not just because both films centered around the central figures of George W. Bush’s presidential administration.

This is not a compliment. Stone’s “Nixon” was an epic and operatic profile of its president due to Stone’s stylized direction and Anthony Hopkins’ powerful performance. But “W” felt like a series of Saturday Night Live skits, albeit armed with cinematic production values and an A-list cast.

McKay’s tendency to break the fourth wall with breezy asides, which he put to such effective use in “The Big Short,” gives him more flexibility than Stone in his own profile of former Vice President Dick Cheney. But he’s still hindered by a lead performance from Christian Bale — a proven acting talent in so many other roles — that has finally forced me to offer the following public service announcement:

Mimicry is not acting.

Hopkins wore a wig to simulate Nixon’s Joseph Cotten finger-wave hairstyle, and did an attempt at Nixon’s Whittier accent that I’m sure sounded close enough to Californian for a Welshman, but otherwise focused on delivering an Anthony Hopkins-quality acting performance.

By contrast, while I’m sure Bale has already earned himself a place in the method acting hall of fame for all the weight gains and losses he’s made for various roles, by concentrating so much on the outer mannerisms of Dick Cheney, he’s turned himself into an uncanny valley caricature of the man.

While Bale’s ability to physically mold himself into a Cheney-shaped package is impressive in its own right, it ironically makes his acting feel less authentic.

On the flip side, while I can’t imagine a better casting choice for George W. Bush than Sam Rockwell, Rockwell’s actual performance is such an aw-shucks, reflexively chuckling self-parody that it lowers the level of the whole film.

There are merits in what remains of this film. Amy Adams delivers a surprisingly compelling portrait of Lynne Cheney as the motivator for a husband who’s initially portrayed as a remorselessly mediocre lummox. Steve Carell brings his typically energetic magnetism to his depiction of Donald Rumsfeld as an amoral, tone-deaf gargoyle who finds it laughable that political power should be wielded for any reason other than power’s own sake.

And McKay is even more boldly experimental than he was in “The Big Short.” He uses narrative asides to explain the context of events. And he plays with how biographical films are enough of a well-worn sub-genre of film to have their own set of familiar cliches and tropes. He pokes fun of those films’ exposition-as-dialogue, which rarely happens in real life, and even pulls an end-credits fake-out midway through the film that made me laugh out loud.

There is something compelling in McKay’s framing of the relationship between Cheney and Rumsfeld, who are cast here as something like Palpatine and Anakin Skywalker in the “Star Wars” prequel trilogy. The relentlessly pragmatic Cheney is shown learning from the ruthlessly acquisitive “Rummy” that anything or anyone in the way of advancing one’s goals needs to be cut out of one’s life.

This cold-blooded calculation damages not only those two men’s friendship, but also Cheney’s relationships with his daughters.

For all its promise, the film goes off the rails. Even as one that doubles as a political screed, the choice of narrator — no spoilers — goes over the top. Also, Cheney’s final monologue, clearly meant to evoke the conspiratorial rants of Richard III, feels instead like a malevolent talking-head interview segment from “The Office.”

I wouldn’t mind seeing a suspension of movies about the Bush White House for the foreseeable future. On paper, it’s the perfect subject for a political film, but it’s already defeated two otherwise talented directors. So maybe we should let it rest for a while.