You Do Need power plug adapter while traveling from Saudi Arabia to Cayman Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Cayman Islands are A and B and in Saudi Arabia is G. This is how they look like.

Saudi Arabia

In Saudi Arabia, outlets of type G are in use.

Type G

Cayman Islands

In Cayman Islands, outlets of type A and B are in use.

Type A

Type B