Possible Clues:

• Get one's feet wet
• Might it be drink that makes a present of 26 across?
• Clandestine, furtive
• Might be this and 20 down for a drink to start with
• Israeli prime minister, d. 1992
• Menachem --, Israeli statesman and Nobel Prize winner
• Command following a countdown
• Start, say, filling waste container
• Launch into
• Cue at an audition