Duplicate your person layer.
Freeze it on the frame you want.
Mask them out. Feather the back end quite a bit.
Desaturate it (Tint effect, Hue/Sat, whatever)
Animate it moving away.
Mess with the blend mode and opacity.
Add a Turbulent Displace effect.
- The Great Szalam
(The 'Great' stands for 'Not So Great, in fact, Extremely Humble')
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