Safety device for vehicle occupants

The device (13) is in the form of a protective bag (14) for filling with gas, to be folded in the retracted state to form a packet (15) and to extend along an inner side of a lateral plate in the inflated state for impact protection for an adjacent occupant. The packet of the protective bag is fully recessed within the door body (9) and the bag unfolds from the door towards the roof when inflated.