Yes, thats right. Sarah (a deranged woman) goes on the rampage in Summer Bay after her boyfriend Felix dies. Felix was previously stalking Dani. Anyways, Sarah finds Tasha's gun and holds Jesse hostage at Irene's place, detirmined to find out who killed Felix. However, eventually Sarah realises that she killed Felix. Sarah leaves the gun behind at Irene's.
A few weeks later, Sarah escapes from the mental hospital and heads for Summer Bay., having forgotten that she killed Felix! Sarah is detirmined to find out who killed Felix (not realising that she did it) and goes looking for the gun at Irene's place. Detective Peter Baker gathers everyone whom Sarah might be after at the Surf club in order to get them to a safe house. Since Sarah doesn't know Leah, Leah offers her house as the safe house.
So sally, Flynn, Noah, Hayley, Jesse, Leah, Kirsty and Kane all go off to the Leah's house. Scott and Dani were supposed to go off with them but Beth told them to go to Paris instead. Scott and Dani accidentally leave their passports behind and go back to their house, where Sarah is hiding. Sarah forces Scott to tie Dani up at gunpoint and forces Scott to take her to Leah's house.
So Sarah holds everyone hostage there, including Peter Baker, whom Sarah hits over the head. Sarah gives Felix's killer 30 minutes to fess up. Later on, Rhys and the police find Dani and race over to Leah's house. Dani runs towards the house and then screams as several shots are fired. H&A then went on two weeks break during the Olympics.
In the next episode, it opens with Noah's memorial service. It is revealed that Noah, Kane etc tried to grab Sarah, but she managed to get away and run out of the house. At this point, Dani was running towards the house and Sarah was about to shoot her. But Noah did something and Sarah ended up shooting Noah instead.
Also, Peter reveals to Leah that Vinnie is alive when they are being held hostage.