on the double (?.)

• amain
• apace
• at flank speed
• at the double
• crowded
• double-quick
• double-time
• expeditiously
• fast
• hand over fist
• hand over hand
• hard-pressed
• hard-pushed
• hard-run
• hastily
• hell for leather
• hell-bent
• hell-bent for election
• hurried
• in double time
• in double-quick time
• in high
• in high gear
• in seven-league boots
• lickety-cut
• lickety-split
• post
• posthaste
• pressed
• pressed for time
• promptly
• pushed
• quick
• quickly
• rapidly
• rushed
• snappily
• speedily
• swiftly
• trippingly
• under forced draft
• whip and spur
• with all haste
• with giant strides
• with rapid strides
• with speed