a (piece|slice) of the action

tendency to take part in an activity started by someone else to receive a share of its profits

The idiom "a piece of the action" has its roots in colloquial language and is thought to have originated in the mid-20th century. It draws from the world of business and entertainment, where "the action" refers to the exciting or lucrative part of an endeavor, such as a profitable business venture or a successful event. It typically used to convey a sense of wanting to participate or benefit from an opportunity or enterprise.

He's always eager to get a slice of the action whenever there's a new startup opportunity in the tech industry.
When the restaurant business started booming, everyone wanted a piece of the action by investing in the trendiest eateries.
As soon as news of the new movie project broke, several actors and actresses were vying to get a slice of the action by auditioning for roles.
The local artists were excited to have a piece of the action in the city's art festival, showcasing their talent to a wider audience.
In the competitive world of sports, athletes strive to get a slice of the action by securing endorsement deals and sponsorships.