Odds On is an exemplar of the way online theatre has developed in the past few years. Dante Or Die’s interactive production is both for and about the virtual world, with a focus on its addictions, using the techniques of film and the aesthetics of gaming.

Written and directed by Daphna Attias and Terry O’Donovan, it feels gimmicky at first: we choose a user name and avatar before clicking to spin the reels in a computer game. It is a significant way to enter the story of Felicity (Fiona Watson), a retiring GP who becomes slowly dependent on an online gambling game. We see her in her final days at the office followed by a new life at home, looking after her baby grandson, Noah (Oshy Fuller), while her son (Elan James) and daughter (Bianca Stephens) bustle in the background or dial in for Zoom calls.

All the while, a game called Pearls of Fortune is superimposed on the screen to suggest that it is omnipresent in Felicity’s life, its tinny Calypso beat accompanying all that she does. We see how the game becomes a casual but compulsive form of gambling, with a ticker at the top of our screens capturing the points she has scored and the sum of money she has won or lost.

Shot on various locations using an iPhone, and running 30 minutes, it seems tailor-made for a generation of Candy Crushers with attenuated attention spans. Yet it carries a punch far beyond its bite-sized storyline, partly because of the immersive nature of Felicity’s game, and also the interludes of animation (directed and edited by John Brannoch) used to heighten the emotional highs and lows it brings.

As Felicity becomes ever more addicted, she falls into the game itself, turning into her octopus avatar. This has a cute and comforting Finding Nemo quality but also shows the insidious ease with which the stakes are raised in online games, and its numbing lure to Felicity, who is played by Watson with convincing vulnerability.

There is an especially powerful moment when she describes how overwhelmed and bewildered her retirement has made her in a conversation with her husband, Joel (Maynard Eziashi), who transforms into an animated dolphin as she talks. It takes a while to realise that this is part of her fantasy world and that confiding in him about her furtive gambling is just wishful thinking.

The animations and haunting soundtrack – composed by Yaniv Fridel and Ofer (OJ) Shabi, with sound design by Ben Kelly – have a naive kind of power and the film’s final, beautiful aerial shot of sea waves and open skies gives us hope for Felicity while leaving the story open-ended.

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