Pick up the medikit from Jekyll's desk and possibly the bottle of ether from the lab (not greatly useful).
Leave the office, turn left (evading or killing the female lunatic) and exit via the door at the end of the corridor (it's the only one which opens).
You need to kill the three lunatics to set the nurse free. He then gives you a key which you can use to exit the level via the door on the left of the large blackboard
Rush straight to the end of the corridor, and kill the lunatic who's lying in wait for you around the bend.
Only one door opens, so you can't go wrong.
When you reach the kitchen area, there's a lunatic waiting for you, but you don't have to kill him.
Once in the canteen, avoid the plate-thrower by using (action button) the dresser (on casters) to protect yourself or by sticking close to the right-hand wall.
You then need to either kill the female lunatic or avoid her by climbing onto the tables at the back in order to make your way to the exit door.
Remember to take the handle from behind the curtain on the left as soon as you enter (it's vital during the next level).
Retrace your steps and go round the partitions to the right. In the second recess, you will see one bed in the normal position and another placed up against the partition. Use one to jump to the other and thereby climb over the partition.
Get down carefully on the other side and continue on your way as far as the madwoman (you don't have to kill her). Climb onto the bed alongside her to gather momentum in order to jump onto the bed in a vertical position.
All you need to do now is to run straight ahead towards the exit while watching out for potshots from the plate-thrower on the partition. Before leaving, take the medikit from the edge of a bed - you are sure to need it sooner or later.
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