Show the vessel to me that I'm to go in (9)
I believe the answer is:
pantomime
'show' is the definition.
(I've seen this before)
'vessel to me that i'm to go in' is the wordplay.
'vessel' becomes 'pan' (vessel or container for cooking).
'that i'm' becomes 'im' ().
'to go in' indicates putting letters inside.
'me' enclosing 'im' is 'mime'.
'pan'+'to'+'mime'='PANTOMIME'
'the' acts as a link.
(Other definitions for pantomime that I've seen before include "Farcical situation" , "farce" , "'Cinderella', for example" , "eg 'Mother Goose'" , "Traditional Christmas stage show with Dame" .)