A Massachusetts mom won’t soon forget this traffic stop.

Darlene MacAllister said she knew she was “speeding a little bit” when she was pulled over by three Hanson police officers. What she didn’t know was that the three cops were just there to distract her as her soldier son snuck up behind her.

PV2 Alan MacAllister had just called his mom to tell her that his flight was canceled and he wouldn’t be coming home to see her.

All the plotting was well worth it to see the look on his mom’s face, MacAllister told WCVB.

“It was just one of those looks,” he said. “Like, you're so happy and so pissed off at the same time. I got her.”

The Hanson Police Department posted the memorable moment to their Facebook page. Watch the sweet surprise below.

Not all traffic stops are negative! Welcome home PV2 Alan MacAllister! We were honored to assist in reuniting Allan and his Mom, Darlene today.

Posted by Hanson Police Department on Monday, June 29, 2015

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