Dry Needling?

What is this?



I went to a physiotherapist (went to a doctor first ofc), had him check my hamstring and shoulder injury and he told me that he wanted to treat me with Dry Needling.



I'm already pretty suspicious of physiotherapists, but when he mentioned Dry Needling I can only imagine my face looking like this







Anyway, I'm just curious to know whether this method is legit and/or if I should find another physiotherapist.