PDQ
amain
apace
at once
away
by forced marches
cursorily
decisively
directly
earnestly
expeditiously
feverishly
forthwith
furiously
hand over fist
hastily
helter-skelter
hotfoot
hurriedly
hurry-scurry
immediately
in no time
in passing
instantaneously
instanter
just now
just then
momentaneously
momentarily
momently
now
on the dot
on the instant
on the nail
on the run
on the spot
pell-mell
pressingly
pretty damned quick
promptly
pronto
quickly
right
right away
right off
slapdash
smartly