The episode starts with one of the creepiest opening scenes in the entire series, with a little girl being greeted in her room by her 'imaginary friend,' Mojo. It's quickly revealed that 'Mojo' is actually a small-time thief who uses an invisibility suit to steal jewellery and visit his young daughter, whom he's forbidden from seeing. Of course, like most criminals who get out of jail and don't learn their lesson, this guy has some devious plans to steal his daughter away from his ex-wife.
This episode takes the fears every parent has, and uses them to great effect here to create an unsettling mood and a REALLY dark plot. Shirley Walker's amazing score doesn't just add to the disturbing atmosphere, either, because aside from the colour palette and themes, it IS the atmosphere! But holy crap, the score is amazingly creepy, it's hard to accurately put into words how good it is. Walker was known for providing separate scores for each individual episode while still maintaining key themes. Her music rarely fails to bring an episode up, and this episode has some of her best work. Even in a series as well-made as this one, with excellent EVERYTHING 95% of the time, this episode's score stands out.
Despite its darkness and spine-tingling moments (literally, it creeps ME out more than any horror movie ever could so far), 'See No Evil' also has a few of the season's funniest moments, which don't detract from the overrall quality or atmosphere of the episode. I won't spoil them, but you'll know them when you see them. The animation quality is also high, in a cartoon series that is known for its budgetary problems and fluctuating animation quality. Thankfully, it seems that the creators know when they've got a gem and when they've got a throwaway episode, because the animation quality seems to follow the patterns of story quality. 'Heart of Ice,' 'Beware the Gray Ghost,' etc. have outstanding quality, while a few others, like 'The Underdwellers' and 'I've Got Batman in My Basement,' have poorer quality. I'm glad the creators know when to pinch their pennies and when to dish it out.
So yes, it's good. 'See No Evil' is one of the best episodes in the first season box set. It doesn't stand as THE best episode of the season, since there are SO many good episodes in this season alone, but it definitely stands out as one of them.
