With its fresh, contemporary version of The Little Mermaid, the Bristol Old Vic (BOV) shows yet again that when it comes to children's shows it is almost peerless. Director Simon Godwin and adaptor Joel Horwood have fashioned a version that, when it gets in its stride, provides a whiff of fear, a lot of laughter and a moving love story. Hans Christian Andersen's tale tells of a mermaid, the youngest of five sisters, who, when she is finally allowed a day of freedom to see the world above, rescues a drowning prince with whom she falls in love. However, others have very different plans for the prince.

The cast is outstanding, with many in multiple roles, even the briefest of which is vivid and memorable. Katie Moore is an affecting and feisty Mermaid, a young woman not afraid to question authority and willing to sacrifice everything for the chance of freedom. Her inability to speak and the agonies she undergoes when she walks on land are powerfully conveyed (marvellous work also by sound designer Gregory Clarke). Tristan Sturrock is moving as the father who watches helplessly as his daughter grows away from him and who can never quite say what he wants to say; he also offers a brilliant turn as an obsequious MC in the second half. Beverly Rudd almost steals the show as an eminently hissable Sea Witch, Queen of Almost Everything, who'd like to be Queen of even more. Billy Howle is very sympathetic as the diffident Prince, unsure of everything and far from being the master of his fate. The couple's growing love is beautifully portrayed.

Jon Bausor's extraordinary design is one of the stars of the show, with its porthole framing the whole action and its boat that rises and sinks creating fabulous stage pictures. Shlomo and DJ Walde's music adds greatly too, though one or two of the earlier numbers have an oddly American MOR feel to them. The musical competition of the second half is one of the comic highlights of the evening. Godwin's direction shows a sure touch: he elicits superb performances and the changes of mood from comic to scary to thoughtful to moving are well judged.

This is a show with big themes but a light touch. It deals with the importance of following your dreams, of daring to say no and of asking questions. It shows the trials of being a parent, the risks of choosing freedom and the giddy confusions of falling in love. The BOV recommends this show to sevens and over, which feels about right, though if my children are anything to go by it is not the murderous villain who has them covering their eyes in horror - it's the sight of grown-ups kissing on stage. The audience loved it; the BOV has another it on its hands.

The Little Mermaid plays at Bristol Old Vic until 18 January 2014.

- John Campbell