From the Super Mario Wiki
Retrieved from "http://www.mariowiki.com/index.php?title=The_Lab&oldid=1731162"
The Lab is a room in Luigi's Mansion. It is here that Professor E. Gadd informs Luigi about the mansion and its ghosts near the beginning of the game, and later provides information on Boos. This is also where E. Gadd asks the player where they want to go; to the Mansion, the Training Room, the Gallery, or, once the game is beaten, the Hidden Mansion.