Often in various films you can see the symbol of the inverted Crucifixion. And there is always some kind of out-and-out indecency going on around in the form of witchcraft, bloody sacrifices or other terrible nightmares. For many years, the symbol of the inverted cross has been introduced into the consciousness of an ordinary person who is far from religion, as a symbol of Satan and all the devils of the underworld.
The inverted crucifix carries a sense of extreme disrespect for the Christian religion and can be used to represent the powers of Satan. The differences between the cross of St. Peter and the inverted crucifix are sometimes obscured, leading to confusion over the acceptability of each symbol.
However, in reality it is a symbol of Saint Peter - one of the 12 apostles and a disciple of Jesus. As you know, on the night after Jesus' arrest, Peter, as Jesus had predicted, showed weakness and, fearing to incur persecution, denied Him three times before the cock crowed. But later Peter sincerely repented and was forgiven by the Lord.
During the emperor Nero's persecution of Christians, the Apostle Peter was crucified on an inverted cross in 64 year upside down at his request, because he considered himself unworthy to die the death of his Lord.
The Apostle Peter is considered the founder of the Catholic Church, therefore the symbol of St. Peter - an inverted cross, is depicted on many Catholic relics and even on the throne of the Pope.