Without anything new and not much of a script Aquamarine just floats by on the screen. The young performers Emma Roberts, Joanna JoJo Levesque and Sara Paxton are attractive enough but the story which ends up being about parents understanding kids is universal in that the fish father is as blind as the human.
Director Elizabeth Allen feeds us a couple of music videos to fill space and time as the two human girls work to help Aquamarine (Sara Paxton) hide on land and in the bathtub. All of this because dad wants her to marry a fish nerd while she has eyes for lifeguard Jake McDorman.
Lightening strikes in the night and when Aquamarine spends time on land and dries off, legs grow in place of her tail. Dark brings back the tail.
There are the usual click gang which look a little more obnoxious in this one that others like it and the big line is "there's something fishy about her."
Missing from this mermaid script is the plot and fun of two preceding films about girl fish. Ann Blyth's free wheeling giddy 1948 role in Mr. Peabody and the Mermaid and Daryl Hanna's lead in Splash with Tom Hanks in 1984.