incredible

So implausible as to elicit disbelief; unbelievable.

Astonishing, extraordinary, or extreme.

Not credible; that cannot be credited; surpassing the possibility of belief.

Surpassing belief as to what is possible; hard to believe; unimaginable; inconceivable.

Not credible; surpassing belief; too extraordinary and improbable to admit of belief; unlikely; marvelous; fabulous.