Old fools to perform with sailor and detective on Saturday (7)

'old fools' is the definition.
The answer and definition can be both people as well as being plural nouns.
Maybe they are linked in a way I don't understand?

'perform with sailor and detective on saturday' is the wordplay.
I cannot quite see how this works, but
'perform' could be 'do' (both can mean complete an action) and 'do' is present in the answer.
'sailor' could be 'tar' (slang term for a sailor) and 'tar' is found in the answer.
'detective' could be 'ds' (detective sergeant) and 'ds' is found within the answer.
No letters remain.
This may be the basis of the clue (or it may be nonsense).

'to' is the link.

Can you help me to learn more?