Those familiar with Only Connect will know how this works. but a quick explanation will not go amiss.
You will see four phrases, one at a time. The first is below, and the other three will be revealed at hourly intervals. You have to work out the connection between the four phrases. Obviously, the more that you see, the easier it should be.
The first one is:
Grandmother in Caernarfon
Answer at 9.00 on Monday