Some wonderful ideas.
[You know, for a moment there, I thought there was a new 'Trapped' game and got all excited. Then I noticed it was a movie and watched it out of curiousity.]
selected aspects (rated from ----- to +++++)
(note: I'm not rating everything or trying to break the flash up into constituent parts. Just indicating how much each adds to/detracts from my enjoyment of this.)
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+++: the slapstick comedy is brilliantly timed. Even when watching it a 2nd time, you had me chuckling away at the stick hitting the stickman.
++: graphics are rather attractive. Various styles used to good effect. I like the spot where his leg breaks and the point where he 'powers up' with the stick and the kanji appears. (What does the kanji say, by the way?)
++: the fact that the 'cage' opened was a surprise.
++: the ending was satisfying and brought some thought-provoking elements to a slapstick comedy.
+++: Wasn't lengthened beyond its natural lifespan, so to speak.
++++: Music was brilliantly chosen.
-: The gun doesn't really match other graphics, with its thin fiddly outlines.
-/2: the square 'stop' symbol in the playboack thing should be a 'pause' symbol.
-/2: Whilst I'm niggling, I think the fwd/rwnd buttons should continue to advance/reverse through frames whilst the button is held down - not just on (press).
-: I'd have liked to see the whole ending explored a little bit more.
--: When we see the stickman crying, it looks strange and a little crappy.
-: The 'victim' could be more expressive. Consider using a simplified and stylised character , but one that has facial features. You do a really good job with the motion, limping and whatnot though. And maybe if you used a dude with facial features, we wouldn't be able to project our own selves onto him... maybe a stickman is better...
overall
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Really, this is brilliant. A laugh followed by a bit of thoughtful reflection. There's parts I can niggle at but this flash is going to haunt me forever.
The stickman struggled to break free of his cage. I personally thought all his attacks were being mirrored and perhaps a possible answer would lie in pulling it, so it pushed itself out, or something. In any case, the attacks were reflected, to comic effect, until the surprise ending, where he does indeed break free, but we realise that we never questioned what was beyond, just as the stickman never did.
Fucking hell, man, I've been trying to work out what to give this - 8, 9, 10... as I wrote the last paragraph, I realise.
I hope you realise I don't give out 10s lightly.
This is gonna stay with me as a concept and an image probably for the rest of my life.