Lear’s beginning to enter stage and I’m keeping close to you – powerful stuff (9)
I believe the answer is:
plutonium
'close to you powerful stuff' is the definition.
I can't judge whether this definition defines the answer.
'lear's beginning to enter stage and i'm' is the wordplay.
'beginning to' says to take the initial letters.
'enter' is an insertion indicator.
'stage' becomes 'put on' (as in putting on a show).
'and' is a charade indicator (letters next to each other).
'i'm' becomes 'ium' (I can't explain this - if you can you should give a lot more credence to this answer).
The first letter of 'lears' is 'l'.
'l' inserted into 'puton' is 'pluton'.
'pluton'+'ium'='PLUTONIUM'
'keeping' acts as a link.
Can you help me to learn more?
(Other definitions for plutonium that I've seen before include "Nuclear material" , "Radioactive element" , "Fuel for nuclear reactors" , "Radioactive material, Pu" , "sign of this bomb-making material" .)