Transcendence Johnny Depp, Rebecca Hall, Paul Bettany. Directed by Wally Pfister. Rated PG-13. Opens Friday.

Arthur C. Clarke famously said that any sufficiently advanced technology is indistinguishable from magic, but good science fiction makes its advanced technology feel like something that could conceivably be developed from what we have currently. Sci-fi thriller Transcendence begins in what appears to be the present day, or very close to it, with scientist Will Caster (Johnny Depp) on the verge of breakthroughs in artificial intelligence. So when Will is poisoned by anti-technology terrorists and decides to upload his consciousness into a computer before he dies, it’s only a small leap from the movie’s starting point.

From there, however, things get out of hand in a way that screenwriter Jack Paglen and director Wally Pfister have trouble getting across convincingly. Will (or the artificial intelligence that shares some of his personality) soon begins expanding his powers at a rapid rate, manipulating his emotionally vulnerable wife Evelyn (Rebecca Hall) into helping him construct an extensive underground lair, from which he can reach his virtual tendrils into all of human society. By the time the movie gets to nanobots in raindrops, it’s completely abandoned any grounded sci-fi.

There are plenty of questionable leaps of logic in the story, which get more implausible as Will’s schemes become increasingly grandiose. The movie posits cyber-Will as a potential destroyer of humanity, but apparently only a small group of people actually know and/or care about his massive technological advancements. Eventually, the story climaxes with some half-hearted action sequences that seem out of place in a movie that wants to be about heady philosophical questions.

Then again, Transcendence isn’t nearly as smart as it first appears to be, peddling familiar anti-technology talking points that could have been lifted from a movie 20 years earlier. Pfister, a veteran cinematographer making his directorial debut, assembles an impressive cast that also includes Paul Bettany, Morgan Freeman and Cillian Murphy, but their characters are all paper thin, and the central relationship between Evelyn and Will has no vitality (Depp is mostly relegated to a computer projection and/or disembodied voice after the movie’s first act). Transcendence tosses out some intriguing ideas, and then spends the next two hours completely squandering them.