I heard the expression "в руки мне" (=into my hands, genitive plural) in a song. As far as I know, to say "into" we have to use accusative case. But in that expression it is in genitive case. Can we rewrite that expression like:"в Мой рук" (accusative plural) ?
Let us see where your confusion starts.One hand is рука, the genitive from it is чего?руки, the accusative is во что? в руку.And all these are singular.
Now two hands is руки(nominative ),нет чего? рук (genitive plural),во что? в руки (accusative plural).
Рука is feminine, so it can't be *мой--accusative singular +рук (genitive plural ).В руки is correct.
Are you talking about this song? https://www.youtube.com/watch?v=UGSBJXxmbNg
Songwriters and poets usually have a freedom to bend regular grammar rules, so their texts sound better. Thatswhy songs and poems can hardly be translated literally. I would definitely not learn russian grammar from song lyrics, esp. from old folk music.
As V.V. said, "в мой рук" is definitely wrong. Read his answer for the correct explanation of grammatical cases.
I heard the expression "в руки мне" (=into my hands, genitive plural) in a song
It means "Give me in [my] hands". "Мне" is Dative and "в руки" is Accusative plural.
Can we rewrite that expression like:"в Мой рук" (accusative plural) ?
It seems you just confused which form is which. "Рук" is Genitive plural, not Accusative.