She showed up for a night of “sex to change the course of the world.” He locked the door behind her and duct-taped the air vents to save the human race. With a careful calculation of comet speed, fish sleep and personal hunches, biologist Jules has pinpointed the cataclysmic end of the world at about 7 minutes away, setting us up for a comedy that takes us for a philosophical swim through evolution and imagination.

In boom, author Peter Sinn Nachtrieb, an up-and-coming playwright with degrees in both theater and biology, has crafted a funny new spin on Armageddon. Gone are the trench coats, zombies and swirling black dust storms of your run-of-the-mill end-of-the-world tales. Nachtrieb offers his musing on one set, with a small cast of three people and four fish.

The play is about much more than the last hope of the human race. It is about the beauty and randomness of the natural world. It is about youth angst, about relationships, about how we mythologize our own origins. If this all sounds somewhat cryptic, it is in your best interest not to know too much about the play before seeing it. Discovering boom’s many layers is key to its entertainment.

A three-person cast can be tricky because if one actor is off or miscast there’s nowhere else to look. This small group delivers. Tara Wibrew is the sort of smart young actress who only seems to take roles that she can be sure of executing brilliantly. Her Jo is layered and compelling. John Jeffrey delivers strong physical comedy as Jules. Walking away with our hearts is Ellen Chance as Barbara. She is so steadfastly normal and extraordinary. The fish are fine.

Competently directed by Bobby Vrtis, the 90 minutes of boom slip past in suspenseful wonder of what will happen, and what is happening. Boom is very, very funny, but don’t expect to walk away with a fuzzy, feel-good buzz. Nachtrieb’s particular brand of existential, biological mythology will have you pondering long past the curtain call.

Boom runs through June 22 at Oregon Contemporary Theatre; $12-$26.