Overall, I just found
Inspector Gadget to be a boring game. The levels are dull, overdone and long. In fact, just about every level is the same, only instead of climbing the Statue of Liberty; you will climb to the top of Big Ben. Basically, this is your standard, run-of-the-mill platformer. Before each mission, The Chief gives you a mission briefing saying that one of Dr. Claw's machines needs to be destroyed - and it is up to Inspector Gadget to get the job done.
For those who remember the show, you know that Inspector Gadget rarely solved the case on his own...okay, I'm lying to you, he NEVER solved the case on his own; it was always his dog Brain and niece Penny. The game is no different and during each level you will have to switch to either Penny or Brain to solve certain puzzles. This was probably the best part of the game and I was disappointed to see that it was not used more. I really would have liked parts of levels dedicated to using just one character and their special skills instead of having to use Penny to get through one door, or Brain to pass up one group of bad guys. Actually, there are parts that you are expected to use a different character, but can easily pass with another.
Inspector Gadget also offers a three-player link mode that has you completing levels against your friends, similar to the mode found in Sonic Advance. This mode is okay, but like the rest of the game, it becomes stale rather quickly and ends up feeling like an after thought.