Poor old Al Haskey (Ian Midlane). His mother Eve (Rachel Bell) remains gravely ill with Legionnaire's disease this week. Feverish and distressed, Eve keeps rambling on endlessly about water babies and fairies.
Al grows more and more anxious about her. Is she just delirious? Or is she trying to tell him something?
It takes Valerie (Sarah Moyle) to realise that Eve is probably referring to the nearby Sprite Trail. Could this be where Eve picked it up? Valerie picks up a leaflet and together she and Al explore the trail and lo and behold, find something which they both become sure must be the source of the trouble.
The only downside is thar Valerie becomes convinced that she has herself caught Legionnaire's disease in the process.
Al contacts Lydia Palmer (Vicky Hall) who is officially involved in tracing the source of the outbreak, but despite being an old friend of Al's, his recent pushiness has rubbed her up the wrong way and she is slow to chase up Al and Valerie's discovery.
Later, she does, however, and Al and Valerie are proven right!
Not that this news is of much comfort to Al, whose mother lies unconscious on a ventilator.
Al is not allowed to see her and vents his frustrations on a Dr. Hadhira Abbas (Natasha Patel) who tries to assure him they are doing everything they can. Al is distraught about the situation, but Valerie helps calm him down.
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