Goal: Find Eleanor Lamb
Start down the path to Persephone. When you come to the entrance, look to the left to spot a Power to the People weapon upgrade station. Upgrade one of your weapons and then continue into Persephone.
Down the hall past the Vending Machines, turn into the room to the right of the falling water and look on the ground next to the Vent here for an Audio Diary (Selling Ryan Short). Continue down the hall and into the Atrium after collecting the diary.
Don't miss this Power to the People station on your way into Persephone.
Goal: Activate the Quarantine Chamber
Activate the Quarantine Room Controls.
Goal: Defeat the Big Sisters
You're up against two Big Sisters here. This is an easy fight if you have the Hypnotize Plasmid. Even if you don't, the tools you do have should be more than adequate to get the job done. When the Big Sisters appear, equip Hypnotize and hit both of them. Hypnotize wears off in about 30 seconds, so keep an eye on the Sisters. While hypnotized they are a reddish tint; they will return to their normal colour when the effect wears off.
Other than using Hypnotize, there's a pool of water in the middle of the area, which you can charge with an Electro Bolt to momentarily stun the Big Sisters if they're standing in it. There is an explosive container next to the Health Station, which you can pick up with Telekinesis and propel at them. Your Drill is a good choice when only one Big Sister is left standing, especially if you have the Freezing Drill Tonic set. Hit a Big Sister with Drill Dash and then keep drilling. With any luck the Big Sister will freeze, allowing you to effortlessly finish her.
Defeating the two Big Sisters
After defeating the Big Sisters, enter the Quarantine Room to trigger an event.
Goal: Escape the Holding Room
Approach the highlighted Vent and press the A/X button to climb through
Goal: Use the Security Release Lever
Continue to the second highlighted Vent at the other end of this room and crawl through to gain access to Sofia Lamb's office. Use the Cell Block Door Controls in Lamb's Office to complete the goal.
Up the steps across from the controls, look for an Audio Diary (Withholding Visitation) on the chair in front of the desk.
Goal: Find the Big Sister Suit Pieces
After collecting the diary, head up the steps across from the desk and chair to enter the Common Hall. There is another Audio Diary (Blessing in Disguise) on the toy submarine next to the statue here.
Proceed through the door to the left of the diary. You can gather 40 ADAM from the “Angel” here. Follow the arrow at the top of the screen to find the Big Sister Armor. Continue through the next double-door. There is another automatic double-door to your right that doesn't open correctly. Use the Vent next to it to enter the room. You can gather another 40 ADAM from the corpse here. Activate the Circuit Breaker to open the door.
Gather from Angels to earn 40 ADAM.
The Big Sister Helmet is in the repair shop. Look on the same desk next to the stairs for an Audio Diary (Behind Mother's Back).
Up the stairs, approach the group of Splicers and turn left to spot another corpse. Gather from the corpse to gain 40 ADAM, and then continue down the hall. The Big Sister Weapon is in the room at the end of the hall.
Goal: Bring the Big Sister Suit to Eleanor
Once you have all three pieces of the Big Sister Suit, follow the arrow at the top of the screen to Eleanor's room. Before giving her the suit, look under the bed to find an Audio Diary (Freeing Father).
Give Eleanor the Big Sister Suit to complete the goal.
Goal: Pick up the Summon Eleanor Plasmid
Take the Summon Eleanor Plasmid from Eleanor. With this Plasmid you can summon Eleanor to fight by your side. Very handy.
The Summon Eleanor Plasmid will make the last stages of the game a cakewalk.
Goal: Exit the Area
Follow the arrow at the top of the screen back to the Atrium. There are two Leadhead Splicers and two Brutes here. Now's a good time to use that new plasmid. Kill the Splicers and then make your way to the level exit.