"More than meets the eye" is a phrase that means that there is something else to be interpreted other than what can be obviously noticed.

When there is "more than meets the eye" about a certain room, for instance, it may be possible to detect an antechamber. If a person is "more than meets the eye," it means that said person is much more complex than you could deduce from a single meeting, or just a few minutes with him/her. Some people often try to hide their true selves, for various reasons, often dealing with acceptance issues of some form or another.

Even a simple cup of coffee could be more than meets the eye, if you are intuitive enough to detect the bleach someone may have slipped in it.