What does the cryptic crossword clue "Allies report false warning of plot (7,5)" mean?

The definition is "Allies". The wordplay uses an anagram. anagram of ALLIES REPORT = SPOILERALERT The answer is SPOILERALERT.

Allies report false warning of plot (7,5)

Guardian Cryptic #29553 | 11 Down | 2024-11-29 flower