Elderly people in care got involved in cryonics, perhaps (4,7)
I believe the answer is:
cold storage
'elderly people in' is the definition.
The definition suggests a singular noun which matches the answer.
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for cold storage that I've seen before include "State of abeyance - refrigeration" , "State of temporary suspension" , "Being on ice" , "Preservation at low temperatures" , "refrigerator" .)