Love affairs are hard to keep on track, and even more so when one lover is also an involuntary time-traveler, apt to just disappear and re-appear at any point before, during or after the relationship. This is the central ... uh ... quirk of Henry and Clare's otherwise blissful time together (pretty houses, lovely linens, cute dates). Due to a genetic anomaly, Henry just can't stay in one place -- or keep his pants on. (As with the Rapture, losing all of one's clothes is a side-effect of bopping through time.)
Robert Schwentke (Flightplan) has adapted Audrey Niffenegger's novel, and he and his cast play this hybrid of sci-fi and romance with a remarkably straight face. As the besotted couple, Eric Bana and Rachel McAdams adeptly make you (almost) believe this is actually probable.
In most romances, the tension is about meeting and falling in love; here, that drama is replaced with calm, because Clare and Henry know that they are already a couple, or will be a couple, or were a couple. With that resolved, they devote their worry to love's other great anxiety: Are you going to leave?
So, despite the time-travel hoo-hah (which is, as always, a little confusing), the slightly too-sweet film is about how Henry and Clare learn to incorporate this potentially devastating uncertainty into a successful relationship that celebrates the present -- even as it is literally interrupted by the past and the future.
Late in the film, a doctor pops up with an implausible two-sentence explanation for Henry's condition, but this is not a story about science. It's about love, love, love. And as devoted fans of the heart know, true love spans space, time -- and, hopefully, for viewers -- logic.