*Spoiler* What's with the 'lame' plot twist?
It's absurd for the lead man/alien to suddenly forget to walk with a cane or even limp at all. We're supposed to believe he's been in symbiosis right from the earliest stages and has managed to stay in character convincingly all the way through. For him to "forget" about his lame leg is just unbelievable - especially considering that he's now the last survivor and ought to be taking extra care to get away with the pretense.
In fact that's why I looked at this forum - to see if it was just me or if it really is indeed a remarkably inane plot twist that almost sucks all the merit out of the foregoing story (which up to that point is light but entertaining enough).
If the "forgets cane" device was a choice by the movie makers to justify their ending sequence (rather than faithful to the original novel) then I'd say they should have done better, and have treated their audience like idiots. No wonder some people feel almost cheated by this adaptation.