hash of a hash

I have a ripemd160 hash that is the hash of an sha256 hash of plaintext. Is there any way to recover the hex values of the sha256 hash so I can recover the plaintext? To be clear:

1. original plaintext: ???????????? UNKNOWN

2. SHA256 of 1: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx UNKNOWN

3. RIPEMD160 of 2: KNOWN

My question is how to recover the SHA256 hash?