Young and Dangerous 4 (Chinese: 97古惑仔之戰無不勝; Literal Title 97 Wise Guys: No War Cannot Be Won) is a 1997 Hong Kong triad film directed by Andrew Lau.

At the wedding, Chan Ho Nam agrees to travel to Thailand with the other branch leaders of Hung Hing in order to invite Chiang Tin Yeung, Chiang Tin Sang's elder brother, to lead the Hung Hing triad.

While 6 of the 12 branch leaders are in Thailand, Dinosaur, back in Hong Kong, who leads the Tuen Mun area for Hung Hing is assassinated by being thrown over a building by Tiger of rival gang Tung Sing society.

Meanwhile, Chiang Tin Yeung agrees to head back to Hong Kong to lead the Hung Hing society.

He declares that Barbarian and Chicken are given a time period of one month to prove themselves worthy of leading Tuen Muen for Hung Hing.

Barbarian gets support from Fatty Lai, the branch leader of North Point, and it's revealed that Fatty Lai's printing studio was once nearly burnt under the orders of Uncle Bee by Chan Ho Nam, which made them enemies.

Back in Hong Kong, Shuk Fan begins her career as a teacher with the worst students in the high school and she is able to temporarily befriend them.

He hopes to gain his own control of the Tuen Muen area with his own society with Barbarian as his puppet.

Pou Pei is seduced by Barbarian's younger brother's girlfriend and let slip the whereabouts of Yee to her.

That night, Chan Ho Nam reprimands Chicken for participating in an unnecessary election as a branch leader.

Tai Fei replaces Fatty Lai as the branch leader of North Point.

The film ends with Chan Ho-Nam and Chicken Chiu as equal branch leaders.