It's one thing to take an episode of Commander Keen and change the graphics, levels, and text to create something new--after all, that's the basis of all mods. It's something entirely different, however, to take an episode of Keen, elaborate on the ideas posed in it, and create what feels like an alternate episode--an expansion pack of sorts. That, however, is exactly what this mod does.
With a gradual learning curve stretching from average gamer to perfectionist difficulty, Kidnapped Keen does a fine job of integrating the story into the level design, as well as keeping the player on their toes with varied scenery and continually evolving level design.
Wherever the player goes, there is rarely a sense of being lost, and the levels are linear enough to keep the player from getting confused.
However, like many Keen1 mods, Kidnapped Keen falls victim to the IceCannon syndrome--a level consisting of way too many ice cannons (as well as enough points to make dying a non-issue). Later levels demand an almost machine-like level of patience or precision to get through.
Graphics: 6/10
Levels: 9/10 (if not for a few key levels, this may have been a full 10)
Story: 8/10
Keen Factor: 9/10