They were the Three Investigators, and appeared in the Alfred Hitchcock mystery book series. The first was in 1964, and the series continued through 1987, along with German language titles in the 1990's.
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there is no secret entrance
yes
Yes. Bilbo and the dwarves use the secret entrance while Smaug uses the main entrance
In the plaza
look up the question what if there isn't a secret entrance on mt ember, basically its the same thing.
Deep Sea Detectives - 2003 Secret Underwater Caves 2-9 was released on: USA: 19 July 2004
Deep Sea Detectives - 2003 The Confederacy's Secret Weapon 2-14 was released on: USA: 4 October 2004
There is no code. The secret entrance with the maids blocking it cannot be acccessed. Its just there to puzzle people i guess.
Use A SECRET POTION at Junkyard Keeper !The Black HOLe
There are four: yellow on Yoshi Island, green in the cave secret entrance in Donut Land, red in Vanilla Dome 2's secret entrance, and blue in the Forest lake stage's secret entrance.
The lake valor is part of a game named "Pokemon". The secret place is actually located in the middle part of the lake which has an entrance that leads through the legendary Pokemon.
Deep Sea Detectives - 2003 More Secret Underwater Caves 3-8 was released on: USA: 20 June 2005