Doctor's Key & Room 5 Guide
The Doctor's Key unlocks Room 5 and reveals the hidden lore of Animal Hospital. Here is how to get it.
What Is the Doctor's Key?
The Doctor's Key is a special quest item in Animal Hospital that unlocks Room 5, a normally inaccessible room in the hospital. The key is obtained through Ratthew's quest line, which spans multiple shifts and involves fetch quests and lore discovery. Room 5 contains important story information about Rattina (Ratthew's missing twin sister) and her connection to Animal Corp.
How to Get the Doctor's Key — Step by Step
Find Ratthew in the Hallways
Ratthew, the shifty rat in a trench coat and fedora, appears in random locations throughout the hospital between shifts. Talk to him to start the quest line. He will mention his missing twin sister Rattina.
Complete Ratthew's Requests
Ratthew will ask you to find specific items or documents around the hospital. These fetch quests span multiple shifts. Check exam rooms, the administrative wing, and maintenance areas.
Receive the Doctor's Key
After completing enough of Ratthew's tasks, he rewards you with the Doctor's Key. The key is a special item that goes in your inventory.
Unlock Room 5
Take the Doctor's Key to Room 5 (the locked door in the hospital). Use the key to unlock it. Inside, you will find clues about Rattina and the truth behind Animal Corp.
Tips for the Quest
- Talk to Ratthew every time you see him — his location and requests change between shifts.
- Check the administrative wing for Ron from Accounting's misplaced documents — these are sometimes part of Ratthew's requests.
- Room 5 is located in the eastern corridor of the hospital. Look for the locked door with a special keyhole.
- The Doctor's Key is single-use. Once you unlock Room 5, the key is consumed.
- Rattina is Ratthew's twin sister with a direct connection to Animal Corp — she is one of only two confirmed Animal Corp-linked characters (alongside Liz).
Rattina & Animal Corp Lore
Rattina is Ratthew's twin sister and one of only two confirmed characters with a direct connection to Animal Corp (the other being Liz, the journalist added in Harlow's Favorite Update). Inside Room 5, you will find documents and clues revealing what happened to Rattina and the extent of Animal Corp's involvement in the anomaly outbreak.
This quest line is part of the deeper lore introduced in the June 2026 Class Update Pt.2 and expanded in Harlow's Favorite Update. Completing it is recommended before attempting the endgame shifts.
Frequently Asked Questions
Where is Room 5 in Animal Hospital?
Room 5 is in the eastern corridor of the hospital. Look for a locked door with a unique keyhole that requires the Doctor's Key.
Can I use the Doctor's Key more than once?
No. The Doctor's Key is consumed on use. Make sure you are ready to explore Room 5 before using it.
Who is Rattina?
Rattina is Ratthew's twin sister with a direct connection to Animal Corp. She is one of the key figures in the game's hidden lore.
Is the Doctor's Key quest required to beat the game?
It is not strictly required, but it reveals important story context that enriches the endgame experience.