A caller claims to be a family member (or a lawyer/police on their behalf) in trouble, asking for money fast — usually by wire transfer, gift cards, or cash pickup.
A voice can be cloned now from just a few seconds of audio pulled off the internet — sounding right isn't proof anymore.
On video: watch for a glitchy edge around the face or hair, blinking that looks off, lips not quite matching the words, mismatched lighting, or someone who avoids turning on video / holds the camera at a strange angle.
The best defense doesn't depend on spotting the fake: hang up, and call that person back on the number you already have saved for them — never a number the caller gives you.
Ask something only the real person would know — not something a stranger could find by searching online.