The plaintiff can make a motion to extend the time to serve; the plaintiff will have to show he/she exercised due dilligence in trying to serve within the 120 days. There is no point in making a motion to dismiss because the plaintiff can still file the case again if it is within the applicable statute of limitations as the "dismissal" for failing to serve the papers within 120 days is not on the merits.
I am a former federal and State prosecutor and now handle criminal defense and personal injury/civil rights cases. Feel free to check out my web site and contact me at (212) 385-8015 or via email at Eric@RothsteinLawNY.com. The above answer is for informational purposes only and not meant as legal advice.
Unless there is some reason other than "peace of mind", for instance if the suit also involved the filing of a Lis Pendens against your property, there is no good reason to do anything at all until you are served.
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