hot brick
/ˌhɒt ˈbrɪk/noun
1In plural on hot bricks: in a state of anxiety, agitation, or restlessness. Chiefly in similative phrase like a cat on hot bricks.
2In similative phrases, as to drop (a thing or person) like a hot brick: = hot potato.
Origin
Mid 19th century; earliest use found in Female Freemasons. From hot + brick.