Jay Alvarez’s short but galvanizing solo piece “Be Careful! The Sharks Will Eat You!” gives Americans a good-natured nudge. In a poignantly personal way, the actor/playwright reminds us why some people, at least metaphorically, still kiss the ground in gratitude that they made it to these shores.

“Be Careful! The Sharks Will Eat You!” runs through April 22 at MetroStage in Alexandria.

Alvarez began his stage career in Washington, studying with Studio Theatre’s Joy Zinoman and at the Shakespeare Theatre, and working at venues such as GALA Hispanic Theatre and the Kennedy Center (in “Shear Madness”). He divides his time now between New York and Los Angeles, working in theater and television.

“Be Careful!” is in large part a salute to his parents, especially his father, Humberto, who planned and carried out a daring escape from Fidel Castro’s Cuba in 1964 when young Jorge/“Jay” was almost 5. Humberto and his wife, Chiqui, had already sent their two older boys to the United States on an airlift before Castro shut down such operations .

In “Be Careful!” we learn how Alvarez’s father spent a full year planning the escape, which eventually brought a group of 25 family members and friends to the United States. Humberto and Chiqui actually built a new house in Cuba as a way to fool the government into believing they had no intention of leaving. A trusted friend obtained a fishing license for Humberto so he could have a boat. When the government suddenly ordered all fishing boats confiscated, he had to execute his plan weeks ahead of schedule.

The show begins and ends with the same scene, as Alvarez portrays his mother, his father, his childhood self and all the others, stepping into the boat and heading into the Caribbean Sea under dark of night. They are equal parts petrified and thrilled.

In between, Alvarez describes life in 1950s Cuba under the dictator Fulgencio Batista. At one point, he dons Carmen Miranda-style headgear, complete with grapes, to give a taste of old Havana before Castro’s 1959 takeover, where American movie stars mingled with Mafia kingpins in lavish hotels and casinos. Alvarez never implies that life was great for ordinary Cubans under the corrupt Batista. Even his father supported Castro at first. But disillusion came quickly to Humberto. It seemed clear, recounts Alvarez, that the family could not join their two older boys in the United States without stealth.

Alvarez’s saga doesn’t unfold in a straight line but digresses and loops back on itself. An ingratiating performer, Alvarez keeps his audience right with him. Near the end, he recaps the opening scene at double speed to pull the audience back to that moment when the sea, the darkness and the unknown loomed before the escapees. In some scenes, his enthusiasm and emotions, particularly when portraying his mother, are over the top for Metro­Stage’s cozy space. Mostly, though, he keeps you happily along for the trip.

There is no set, really — just a bare stage with two chairs and a large screen at the back on which are projected photos of the group on the boat, and later, an impressionistic blur of the receding lights of Cuba.

Horwitz is a freelance writer.

Be Careful! The Sharks Will Eat You!

written and performed by Jay Alvarez. Directed by Theresa Gambacorta. Lighting and projections, Jessica Lee Winfield; sound, Kelly Ericson Harnett. About an hour. At MetroStage, 1201 N. Royal St., Alexandria. Call 703-548-9044 or visit www.metrostage.org.