Kirkus Reviews is one of the oldest still-operating review services in the country, launched in 1933. In recent years, they have branched out to allow direct-publishing authors to purchase reviews. The reviews are not guaranteed to be positive and they are not cheap, but authors are allowed to keep them unpublished if they are negative.
I think we’ll be publishing this one!:
“…the puzzle pieces click satisfyingly and unpredictably into place. The authors skillfully manage the multiple time frames and large cast, and never leave any plot threads dangling. The book’s science-fiction element drives the major plot twists, but the most engaging scenes are those in which readers learn the real relationships and histories between the characters. A complex thriller that offers new revelations up until the very end.”