In the 1960s TV series "Batman", the switch that opens a hidden entrance to the Batcave is concealed inside a bust of which historic figure?

The 1960s TV show "Batman" was a live action television series that was based on the DC comic book character Batman. In the show, the entrance to the Batcave is behind a bookcase which is activated by a control switch hidden in a bust of William Shakespeare. Bruce Wayne goes to the Batcave to become the superhero, Batman. This cave is Bruce's secret headquarters beneath his personal residence. Batman is very lucky to have the cave; Bruce discovered it only by accident after he bought the house.

Bruce initially used the cave as a sanctum and to store minimal pieces of crime fighting equipment. In time he uses the cave as a stronghold to store a plethora of crime fighting equipment. Also, it becomes a trophy room, a forensics lab, an area with a supercomputer, etc.

In the TV show, Adam West is Batman and Burt Ward is Robin. They are two crime-fighting heroes who defend Gotham City from a variety of arch villains. Batman's secret identity is as Bruce Wayne, a wealthy American playboy, philanthropist, and owner of Wayne Enterprises. After witnessing the murder of his parents as a child, he swears vengeance against criminals. It is an oath tempered by a sense of justice. Bruce will train himself and craft a bat-inspired persona to fight against crime.

This show was known for a simplistic morality; it was aimed at a largely teenage audience. A total of 120 episodes were done, and they aired on ABC for three seasons (January 1966 to March 1968).