(In British accent) Call the police! Your expeditiousness is of utmost importance.
어서 와, 어서 오세요, 어서 오십시오 are NOT(!) rude expressions at all
어서 just means "quickly" / "swiftly" / "promptly"
어서 와 => Literally means "Come quickly" (in a warm, welcoming sense - casual form) meaning "Welcome!"
어서 오세요 = 어서 오십시오 => Come quickly please (in a warm, welcoming sense - polite form) meaning "Welcome!"
Must be like, "o-hairi nasai." Something like, "Come right in, without hesitation." Skip the formal greetings and all . . .
Basically. It means quickly or "hurry and do it" but not in a rude way.
Quickly not in the list, but I would find it to be the most natural translation
I think the translation should say, "Call the police quickly" instead of "Call the police now" because the word 지금 or 이제 is not here.