Invest in a film after the king and knight trade places to get a Russian satellite (7)
I believe the answer is:
sputnik
'satellite' is the definition.
(sputnik is a kind of satellite)
'invest in a film after the king and knight trade places to get a russian' is the wordplay.
I cannot quite see how this works, but
'invest' could be 'put' (synonyms) and 'put' is found within the answer.
'king' could be 'k' (abbreviation for king in chess) and 'k' is found in the answer.
'and' could be 'n' (common abbreviation for 'and') and 'n' is present in the answer.
The remaining letters 'si' is a valid word which might be clued in a way I don't understand.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for sputnik that I've seen before include "First artificial earth satellite" , "Early Soviet satellite" , "First man-made satellite to orbit the earth" , "Soviet space orbiter" , "space traveller" .)