Sends reports of plot discovered in steelworks? (10)
I believe the answer is:
telegraphs
'sends' is the definition.
(to send a telegraph)
'reports of plot discovered in steelworks?' is the wordplay.
I cannot quite see how this works, but
'plot' could be 'graph' (graphing is a kind of plotting) and 'graph' is found within the answer.
This explanation may well be incorrect...
(Other definitions for telegraphs that I've seen before include "Signals" , "Newspapers" , "Gives easy-to-read indication of what's to come" , "papers" .)