Green’s Dictionary of Slang

spell n.1

[Ger. spiel, to play]

a theatre.

[UK]J. Poulter Discoveries (1774) 43: Pike to the Spell; go to the Play.
[UK]G. Parker Life’s Painter 159: Rum squeeze at the spell. A kind of harvest for pick-pockets. When the king goes to the play, and there is an over-flow of the house, the Spell is cant for the theatre.
[UK] ‘Cant Lang. of Thieves’ Monthly Mag. 7 Jan. n.p.: Let us pike to the Spell, Let us go to the Play.
[UK]G. Hangar Life, Adventures and Opinions II 60: Various impositions, practised daily on the unwary [...] such as, [...] a rum squeeze at the spell.
[Aus]Vaux Vocab. of the Flash Lang.
[UK]‘An Amateur’ Real Life in London I 197: Let us proceed directly to Dolly’s, take our chop, then a rattler, and hey for the Spell.
[UK]Egan Finish to the Adventures of Tom and Jerry (1889) 134: And when the Spell is over, to Mrs H.’s she’ll run.
[UK]G.W.M. Reynolds Mysteries of London vol. 2 142: Precious-rum squeeze at the Spell Good evening's work at the theatre.
[US]Ladies’ Repository (N.Y.) Oct. VIII:37 317/1: Spell, a theatre.
[UK]Hotten Sl. Dict.

In phrases

breaking up of the spell (n.)

the end of the nightly performance at the Theatres-Royal, London; as the crowds disperse pickpockets move among them looking for valuables.

[Aus]Vaux Vocab. of the Flash Lang. in McLachlan (1964) 229: breaking up of the spell the nightly termination of performance at the Theatres Royal, which is regularly attended by pickpockets of the lowest order, who exercise their vocation about the doors and avenues leading thereto, until the house is emptied and the crowd dispersed.
[UK]Egan Life in London (1869) 216: As the Spell was broken up [...] they would take a turn to a ‘Sluicery’.
[UK]Barrère & Leland Dict. of Sl., Jargon and Cant.
game of the spell (n.)

(UK Und.) ? pickpocketing.

[UK]‘Poll Tomkinson’ in Convivialist in Spedding & Watt (eds) Bawdy Songbooks (2011) IV 14: Bill Gubbins, he vos a leery cove, / In the game of the spell, fly to every move.