The Last Circus on Earth

The aliens came for Earth. They should have picked a different landing zone. Forty miles from the nearest town, Cirque Phantasmagoria is barely surviving: one tattered Big Top, a handful of desperate performers, and a crew of clowns the world forgot to fear properly. Then the Yarnathi Empire descends from the stars. Commander Lirex expects helpless civilians. Instead, he finds Rictus the fire-breather, Sister Splat the disgraced chemistry teacher, Picklejack the knife thrower, the silent Mime Syndicate, and Jester - the skull-faced clown with an old ringmaster's horn and a talent for turning fear into timing.
The circus is outnumbered, outgunned, and completely unreasonable. Which makes it Earth's best hope. As the invasion spirals into chaos, one truth becomes impossible for the aliens to ignore:A clown who dies onstage does not leave the act. He becomes timing.