Yet another film in which Christopher Nolan had a hand (albeit only as executive producer), so I was looking forward to this. To sum up; I found Transcendence had some good ideas but disappointing execution.
SPOILER WARNING: read no further if you want to watch the film, as this review contains spoilers, starting with a plot summary.
The focus is on Will Caster (Johnny Depp), a genius working on the development of AIs (artificial intelligences), who is fatally injured in an attack by modern-day luddites opposed to the development of such technology. Before he dies, his wife and fellow researcher Evelyn (Rebecca Hall, very good as usual) and his colleague Max Waters (Paul Bettany) upload his mind into a powerful computer. The rest of the film contains multiple plot threads, as the disembodied Will Caster (surely a case of nominative determinism!) gradually extends his reach and power across the internet from a massive underground HQ he creates in a desert town, dramatically pushing forward the boundaries of science. The FBI becomes concerned with his increasing power and joins forces with the luddites to attack the HQ, while Evelyn, who is having increasing doubts about whether the uploaded Will is still her husband or a different being with Will's memories, is being tempted to join them. The climactic decision of the plot is whether or not Will's enemies should upload a computer virus that will destroy him, but at the same time bring about the collapse of our technological civilisation.
First, all credit to the film makers for acknowledging that these developments would be spread over several years rather than within the few days that Hollywood usually assumes that anything important takes, and for exploring some of the existential issues around the nature of a human mind uploaded to a computer. However, these genuine concerns become rather obscured by some silly sub-plots when Will's advanced medical science is able not only to cure people's ailments and immediately repair their bodies, but at the same time make them super-strong, and at the same time give him the power to take over their minds and control them. He also acquires the power to instantly repair any damaged equipment (or to destroy his enemies' weapons) by some sketchily explained means. In one ludicrous later scene a rag-tag band of luddites and FBI agents launch an attack on the vast underground complex using one ancient howitzer and a mortar. Fortunately, the final scenes do redeem the film to some extent.
There are genuine issues about AIs in general and uploading human minds into computers (should that ever be possible) in particular. I briefly explore some of the latter in my article On Immortality on this blog (link in the column on the left). Transcendence has a stab at some of them and is worth watching, but a really adult drama focusing on these issues is yet to be made.