British Transport Police (BTP) are urging a thief to Let It Go after he stole a suitcase containing a rare character costume from Disney film Frozen while the owner slept.
The brazen theft happened on 9 May on a train between Wigan and Birmingham and BTP have now released an image of a man they would like to question.
The owner, a 27-year-old woman from Southport, reported the theft after she arrived at Birmingham New Street and realised her case had gone.
Inside the case was a rare replica character costume from the Disney film Frozen, along with other personal items.
Police believe the man got off the train at Sandwell and Dudley station.
The film - inspired by Hans Christian Andersen's fairy tale The Snow Queen - was an enormous commercial success and its the highest grossing animated film of all time.
It raked in an eye-watering $1.3bn (£830m, €1.15bn) after it was released in 2013 and picked up two Academy Awards for Best Animated Feature and Best Original Song for Let It Go.
PC Andy Stoddart, investigating, said: "A 27-year-old woman, from Southport, boarded a Birmingham-bound train at Wigan North Western station shortly after 7am. She placed her suitcase in the on board racks and sat nearby.
"A short time later the woman fell asleep and only woke when the train arrived at Birmingham New Street. When she checked the rack, she realised her case had gone. Inside the case was a rare replica character costume from the popular Disney film 'Frozen, along with other personal effects."