Their recent collaboration which has been turned into a film was written entirely by the father

It is ironic that this writer uses a pseudonym to separate himself from his father who is perhaps the biggest writer of all time sales wise in the specific genre they both write in. The reason it is ironic is the father has ghostwritten 70% to 80% of the work credited to the son. In fact their recent collaboration which has been turned into a film was written entirely by the father except for the title which was the son’s contribution.