I am puzzled over the following passage from a novel.
(Aubrey suspect Weintraub, the druggist, is plotting to kidnap a young girl, and he looks into his house from the window and sees a savage quarrell between him and his wife.)
Aubrey saw the druggist's pointing finger tremble. Again he ducked out of sight. "That man's face would be lonely in a crowd," he said to himself. "And I used to think the movies exaggerated things. Say, he ought to play opposite Theda Bara."
He lay at full length in the paved alley and thought that a little acquaintance with Weintraub would go a long way.
(The Haunted Bookshop by Christopher Morley)
What I don't understand is the last part: "a little acquaintance with Weintraub would go a long way". Does this mean "if he got acquainted with Weintraub, it would benefit him a lot"? I think this does not make sense in this case. Or does this mean "a little more investigation might bring about an important clue into what Weintraub is doing"? This seems to make better sense than the previous interpretation, but I am not sure.
I appreciate any comments. Thank you.