"The secret mission of infiltration is absolutely new."
Or considering standard usage:
The translation heavily depends on the intended context and fixing typos or supposed errors based on that context. secret mission sennyuu sousakan wa zettai ni new
Assuming a typo or variation, if one replaces or adjust for known manga,"Secret Mission: The Infiltration Operation is Absolutely New" doesn't find direct reference; adjust might reflect. "The secret mission of infiltration is absolutely new