Those Casualty fans forced by the BBC to spend the rest of the summer wondering if good old Maggie will agree to marry dear old Charlie, or if Holby City A&E won’t have been burnt down by a malignant hospital manager before programmes resume, should enjoy most of the National Youth Theatre’s latest offering. One of its best moments has a lovelorn doctor presenting a nurse with a human heart from the fridge as a Valentine’s Day gift. Now there’s a new approach for Charlie should Maggie prove unwilling.

That comes in the first, stronger half of Sean Hughes’s script and John Nicholson’s production. The exuberantly youthful cast hop about saying things all too familiar to us Casualty scholars: “We must get a line in”; “Clear!”; and “I wish I’d spent more time with her.” A jovial doctor tells a patient he’s just kidding for telling her that her results are fine, because actually “we found a malignant cyst”.

Another medico whimsically announces that he proposes to remove a patient’s right lung or her left lung or leave both lungs and remove everything else. This is the NYT’s mischievous salute to the NHS on its 60th birthday.

I enjoyed the episode in which a surgeon, wearing his mask over one eye, does piratical things to his victim with a plastic knife, and the series of episodes in which tactful doctors reduce the news they’re breaking from death sentences to mild colds. I couldn’t see the relevance of the running spoof of 1940s adventures in remote climes, but it’s amusingly done and maybe the idea is to send up that often antiquated medium, hospital radio.

However, the second half is as unfunny as the first is funny. An MP who has come to open an Alzheimer’s lab shows signs of having the disease himself. A hospital virus – an actress in straggly red – capers about but doesn’t have much effect on a ward full of alienated teenagers, one of whom is asked by a flustered doctor for marriage guidance. The script itself begins to feel as aimless as a patient stuck on a trolley in A&E: which is a pity, because there’s genuine fun beforehand.

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