Emma Gilbert portrayed by actress Claire Holt did not appear in this episode; only in a flashback. The first time one of the three main mermaids are absent in an episode although Emma left after season 2.
Easter Egg: When Cleo and Lewis are talking in Cleo's kitchen, 2 photographs of the first generation of the Sleepover Club from Season 1 of the series Sleepover Club (2003) can be seen on the fridge behind Cleo. This implies that the two shows are the same universe.