You have your memory back, you have a little evidence that points to your being framed, and you have what appears to be a combination to a safe. Time to find out if you can clear your name once and for all.
The office safe[edit]
When you return to Peoria Street, head back to Joe's Bar, climb the stairs, and return to the office with the slain body of Joey Siegal. This is where you found a combination safe on the wall. Notes 3 and 4 from you investigation on South Kenzie Street have sequences of numbers. Try to USE each of them on the safe. You will find that Note 3 did in fact contain the correct combination. The safe will pop open. Inside you will find a folder and a box. You will have to OPEN each of them to find out their contents.
Inside the box, you will find a new key. TAKE the key. Inside the folder is another note. TAKE the note and examine it. The note is an I.O.U. claiming that you, Ace Harding, owe Joey Siegal $1,000. There's only one remaining mystery at this point; the trunk of the car outside of the bar. Perhaps the key you just collected can shed some light on that.
The car trunk[edit]
After grabbing the contents in the safe, leave the office, head back downstairs and exit the bar. When you're facing the front of the bar, visit the rear of the car to look at the trunk. If you try to USE the key from the safe on the trunk, you will find that it opens. What you will find inside is one very large woman, tied up and gagged. This must be the Mrs. Sternwood you read about from the map.
You are told that she is unconscious. If you can recall, the file from Dr. Brody's office mentioned a medicine that worked on unconscious people; the Sodium Pentothal. It would be a good idea to try using some on Mrs. Sternwood at this time. In order to do so, you'll first have to remove her gag by using the TAKE command. The USE the dose of Sodium Pentothal that you took from Dr. Brody's office on the syringe/capsule. And finally, USE the syringe/capsule on Mrs. Sternwood. Upon doing so, she will begin to talk and ask to be taken home. She will provide you with an address on Auburn Road. Time to find another cab.
Auburn Road[edit]
You'll want to make sure that you have at least 6 coins before you head out, 3 for the trip to Auburn Road, and 3 more to get back. Ask a driver to take you to Auburn Road. After you arrive and step out of the cab, you will be at what appears to be a mansion. You may notice a mailbox out in front. You can OPEN this mailbox and examine the contents. You will find an envelope. OPEN it and TAKE the letter that's inside. Examine the letter to find that it's the ransom note sent to Mr. Sternwood for his kidnapped wife. MOVE to the front door, and USE the knocker to get someone's attention.
You will be greeted at the door by a butler. If you try to SPEAK with him, he will simply ignore your request to speak with the residents, and slam the door in your face. If you want to make progress, you'll have to be a little less civilized, and HIT him, knocking him unconscious so you can get by.
Once he's out of the way, you'll notice a door on the first floor, and a staircase to the second floor. The door on the first floor leads to a kitchen with a bunch of food and objects that you can examine and take. Although examining the frying pan will trigger a memory of your mother, none of the items in the kitchen are necessary for your investigation. You can safely ignore the kitchen altogether, and simply MOVE up the stairs.
On the second floor, you will reach a hallway with two doors. OPEN both of them. It's arbitrary which one you enter first, since they lead around to another in a circle. Head through the left one, and you will find a woman asleep in a bed. If you examine the room, you may notice a nightstand with some drawers. Open the drawer, and you will find a memo, a ball point pen, and some glasses. The pen is useless, as are the glasses, but do TAKE the memo.
If you examine the memo, you will notice that it has several indentations in it. Time for an old detective's trick: try to USE the pencil on the memo and examine it again. Lo and behold, you will be able to read an entire time table of the job done to frame you for Joey's murder and Mrs. Sternwood's kidnapping! This is a huge piece of evidence, and you'll have to get it to the police in order to clear your name.
At this time, OPEN the door you see on the right and MOVE through it. You'll be in another bedroom with a man sleeping inside. You will find a briefcase on top of another nightstand with drawers. You can open the briefcase, but it's empty. Open the drawer, and you'll find tissues, a candybox, and an envelope. OPEN the envelope, and TAKE the letter that's inside. Examine the letter, and you'll read a threat delivered to Mr. Sternwood by Joey Siegal.
You have everything you need, now you need to get back to Peoria Street and talk to the police. Exit the mansion, hop back in the cab, and return to Peoria Street.
Not so fast[edit]
You should now have everything you need to go to the police and clear your name... however, you also have a bunch of items that will incriminate yourself as an accessory to the crimes. If you want to go to the police and keep your nose clean, you're going to have to find a way to get rid of the damning evidence against you. There's only one place in town that even the police won't bother to investigate: the sewers. It's time you made a trip below the street and lightened your inventory a bit.
From the front of the bar, OPEN the manhole cover on the street. MOVE through the manhole, and then MOVE down into the sewer. MOVE through the pipe, and then MOVE down from the sewer junction. There is a good chance you may encounter an alligator while you explore down here. If you do, simply USE your gun by pointing at its head to kill it. You should find yourself in the deepest part of the sewers.
It's time to start to LEAVE any item that points to your involvement in the crime, starting with the gun that was used to kill Joey and has your fingerprints on them (Gun1). LEAVE the I.O.U. note that you found in the office above the bar (Note1). Also LEAVE the map that you found in the glove compartment indicating where you should go after you kidnapped Mrs. Sternwood (Map). And finally, LEAVE the file you found in the file cabinet in your office detailing the plan to kidnap Mrs. Sternwood (File5). (Make sure you've read every one of the latter items, or the NES game won't let you get rid of them.) As long as you get rid of these items, the cops won't be able to immediately suspect you of wrong doing.
Ending the nightmare[edit]
Once you're done ditching any evidence against you, it's time to return to the surface and make your way to the police. The key pieces of evidence that are absolutely required to clear your name are the memo, the diary, and the ransom note letter (Letter1). If you are missing any one of these, or you are still holding on to any of the incriminating pieces of evidence against you, the cops will turn their focus on you. As long as you have all three, the police's attention will be completely off you and on Mr. Sternwood. Congratulation, you saved yourself and completed the game.