like a shot vs directly

like a shot and directly both are adverbs.

Word	Noun	Adjective	Verb	Adverb
like a shot	No	No	No	Yes
directly	No	No	No	Yes

As adverbs, like a shot and directly are synonyms defined as:

like a shot and directly: without delay or hesitation; with no time intervening

Other synonyms of like a shot include at once, forthwith, immediately, instantly, now, right away, straight off, straightaway.

like a shot (adverb)	directly (adverb)
without delay or hesitation; with no time intervening	without deviation
	in a forthright manner; candidly or frankly
	without anyone or anything intervening
	without delay or hesitation; with no time intervening