The story, set in 2020, is about the first manned mission to Mars, the disaster that befalls its crew, and the subsequent attempt to rescue the surviving astronaut, Mission Commander Luke Graham, played by Don Cheadle. One scene that stands out in my memory is where one of the crew, played by Tim Robbins, gets stranded in space, and the other crew members try to rescue him. The sequence is effective and moving, and gave me a feeling of the frustration that must be felt in such a situation. Another great scene is where the camera takes us on a quick tour of the ship, all in one continuous flowing shot; we go around corners and turn upside down, while watching the crew walking or sitting around in the weightlessness at different angles. Incredible.
The special effects were done by ILM, and I truly believe that this film would have been doomed without them. The hallmark of good special effects are their invisibility, and ILM are masters of that. There is one sequence in which we approach the spacecraft from outside, and enter it through a window, finally ending up inside it. The whole thing is so seamless that it's completely convincing. Other spectacular effects are the sand storm that kills the first crew, and the 3D planetarium at the end of the film.
Overall, I'd say that Mission to Mars is worth seeing if you're a special effects fanatic, but otherwise you'd do better to stay at home and rent 2010 instead.