The rest of the series can be found by clicking on this link to the Only Connect bookmark list.
To solve this one, you need to work out how the images below are connected.
Once you have worked out how things connect, the following questions should be straightforward
Reading from left to right :
A=the number of letters in the person associated with image #1 (3 words).
B=the number of letters in the person associated with image #2 (2 words).
C=the number of letters in the person associated with image #3 (2 words).
D=the number of letters in the person associated with image #4 (3 words, including middle 'nickname').
E=the number of letters in the person associated with image #5 (2 words).
F=the number of letters in the BBC TV programme associated with all the above (4 words).
The cache can be found at : N55 00.Y W001 37.Z
Where Y = F x (A + B - D) + E - C and Z = ((D x C) - ((B + F - A) x E))
You can validate your puzzle solution with certitude.