unaccountable

adj. inexplicable, inaudito, incomprensible

inexplicable

inexplicable, extraño, misterioso; irresponsable, falto de responsabilidad

(adj.) = inexplicable, misterioso, incomprensible
Ex: You read him to the end with a ravenous appetite and rise from the feast with an unaccountable sense of emptiness.

(adj.) = que no tienen que rendir cuentas a nadie
Ex: They describe what it is like to find yourself on the other side of a one-way mirror, innocent but presumed guilty, by professionals who are almost completely unaccountable.