Katy Perry arrives in Sydney using friend as decoy

American singer Katy Perry was able to pull off a decoy trick at the Sydney International Airport when she played the 'personal assistant' to her mystery brunette lookalike friend.

The pair reached Sydney on a Qantas flight from Los Angeles and emerged with a burly bodyguard who was pretending to protect the 'decoy' Katy Perry.

Walking behind her friend, Perry hid under her black beanie and dark shades. Both women wore torn black jeans, shades and matching boots.

While the decoy fooled many fans, some noticed who's the real who and scored a signature from the real Katy Perry, reports News.com.au.

Perry shared a laugh with her friend after waiting paparazzi photographers were busy clicking her friend.

The 'I Kissed A Girl' hitmaker is in Australia to perform in Sydney and Melbourne.