Guy and David are climbing on an artificial climbing designed for indoor vertical climbing wall at JJ's Gym. Jess the proprietor, has fixed part of the climbing wall herself, which has involved screwing a plastic panel onto the wall. Unknown to her however the panel has started to crack. When Guy and David are roped up a massive crack opens up on the wall tearing away Guy's rope causing him to fall on David. Both of them land on a crash mat which is set out at the foot of the wall. David has his hip shattered. Guy is far less injured because David breaks his fall but still suffers from a dislocated shoulder.

Guy is taken to Denmark Hill hospital. Whilst in A&E Guy is given a standard anti-inflammatory drug. This is a non-prescription drug, which has no known side effects and does not require any clinical oversight to administer. Guy, after taking it, has a sudden allergic reaction which causes his chest to seize up. He has never had a reaction like this before and there is nothing in his medical record that would suggest a susceptibility to this reaction.

Nurse Ellison who is on duty in A&E, panics and interprets Guy's symptoms as a cardiac arrest and attempts CPR. It is only after 10 minutes that she realises it is an unusual allergic reaction and uses an anti-seizure medicine which starts him breathing again. Guy however has suffered brain damage due to a lack of Oxygen. An expert report later establishes as a matter of fact that had Nurse Ellison correctly administered the medicine he would have had between a 48% and 53% chance of a full recovery and that this reaction to the drug was completely unforeseeable, and the manufacturers of the drug could not have anticipated what happened to Guy.

David is also taken to Denmark Hill hospital where his hip is reset. Treatment seems to be going well. But unknown to David he has a rare blood condition caused by constant exposure to mercury in his work as a chemical engineer for Karl's Construction. Due to this the blood fails to clot properly around his damaged hip leading to paralysis in his left leg. JJ's Gym deny responsibility for the paralysis of David's leg. Karl's Construction PLC were aware that there were background traces of mercury in the atmosphere at their workplace but assumed any harm was likely to be minimal and argue that such low levels of mercury in the bloodstream couldn't by themselves have caused paralysis.

Advise both David and Guy.