Obviously a Mustang with a Charger front and rear grafted on. Whoever did it, looks to have done an excellent job. I think it looks pretty good, other than the proportions seem a bit off between the Charger front clip and the Mustang body because a Charger is a much bigger car.
Side note: I wish Chrysler would have built a 2 door Charger as an option. I'm sure they'd sell a lot more 4 doors than 2 doors but still...........................