Green’s Dictionary of Slang

cold storage n.1

1. death; thus also a grave or cemetery.

[Aus](con. WWI) A.G. Pretty Gloss. of Sl. [...] in the A.I.F. 1921–1924 (rev. t/s) n.p.: cold storage. ‘To go into cold storage’ – to be killed during the 1916 winter.
[US]Maines & Grant Wise-crack Dict. 15/2: Wooden kimona – Case for cold storage.
[US]L. Pound ‘American Euphemisms for Dying’ in AS XI:3 198: Placed in cold storage.
[US]Wentworth & Flexner DAS.
[US]H. Rawson Dict. of Invective (1991) 92: cold storage. A grave or cemetery.

2. a prison.

[US]A.J. Pollock Und. Speaks 24/1: Cold storage, held in jail by police on no specific charge.
[US]Monteleone Criminal Sl. (rev. edn) 55: cold storage Solitary confinement.
[US](con. 1940s–60s) Décharné Straight from the Fridge Dad.

3. (US) a state of temporary clandestine residence, in order to avoid identification, capture.

[US]F. Kane ‘Return Engagement’ in Best of Manhunt (2019) [ebook] ‘Blesch take care of the old guy I sent over for cold storage?’.