We introduce PE-AONT: a novel algorithm for very fast computational secret sharing scheme. The core idea of this scheme is to encrypt the data only partially before applying an all-or-nothing transform that will blend the encrypted and non-encrypted data. By doing this, we achieve much better performance than relevant techniques including straightforward encryption. To this regard, a performance benchmark is provided. Interestingly, when the ratio between the number of encrypted and non-encrypted fragments is wisely chosen, data inside fragments are protected against exposure of the encryption key unless all fragments are gathered by an attacker. Therefore, by choosing the right parameters, we can achieve key exposure protection, faster processing, and a better overall protection.