the great … in the sky

Từ điển Oxford Advanced Learner 8th

the great …in the ˈsky idiom
(humorous)used to refer to where a particular person is imagined to go when they die or a thing when it is no longer working, similar to the place they were connected with on earth
•Their pet rabbit had gone to the great rabbit hutch in the sky.
Main entry: ↑great_idiom