I am a movie director and I just received the following movie plot. Could you help me answer this question? If not, let me know by writing "Not answerable". Plot title: Kung Fu Hustle Movie plot: Turmoil grips Shanghai in the 1940s. Various gangs vie for power, the most feared of which is The Axe Gang, led by the infamous Brother Sum and aptly named after its weapon of choice. In the absence of law enforcement, people can live peacefully only in poor areas which do not appeal to the gangs. An example is Pig Sty Alley, a tenement home to people of various trades, run by a lecherous landlord and his domineering wife. One day, two troublemakers, Sing and Bone, come to the alley impersonating members of the Axe Gang in order to gain respect. Their plan fails miserably, and Sing's antics attract the real gang to the scene. In the massive brawl that ensues, more than fifty gangsters are defeated by three tenants who are actually powerful martial arts masters: Coolie, Master of the "Twelve Kicks;" Tailor, master of the "Iron Fist;" and Donut, master of the "Hexagon Staff."After the fight, Sing and Bone are apprehended by Brother Sum for causing trouble and publicly humiliating the Axe Gang. The two narrowly escape death when Sing quickly picks the locks on the chains with which they are bound. Sing asks Sum to make himself and Bone members of the Axe Gang. Impressed with his skill at lockpicking, Sum tells them that if they kill just one person, he will allow them to join the gang. The next day the duo return to Pig Sty Alley to murder the Landlady, but fail comically due to ineptitude. The two part ways and narrowly escape from the furious Landlady. Sing is badly injured and hides in a traffic control pulpit, where his injuries spontaneously heal. During this convalescence he unconsciously strikes the steel sides of the pulpit, leaving deep impressions of his hands. After he has fully recovered, he rejoins Bone, but is unable to explain his mysterious healing.Sing and Bone lament their failure on the streets, and Sing describes his childhood. He spent his meagre life savings to buy a Buddhist Palm manual from a beggar with the intention of "preserving world peace." He trained himself, but when he tried to... My question: How can the protagonists obtain membership in the Gang?
The answer to this question is:
If Sum is impressed