Following the cancellation of the American series of The Three Investigators, the series continued in Germany and is known there under the brand name Die drei Fragezeichen or Die drei ??? (“Three question marks”). Although the German version starts with The Secret of Terror Castle, it continues through The Mystery of the Cranky Collector, then picks up with the Crimebusters series and continues on with German-language originals from there (starting at volume 56). The German-language originals started in 1993 with books by Brigitte-Johanna Henkel-Waidhofer. She wrote 16 books for Kosmos until 1996. After her era ended, several other authors continued to write in the series at the rate of six books per year (in contrast to the U.S. series, which published one new story every year or so after Robert Arthur’s death).
In Germany, the franchise has also been the source of audioplays, films, and graphic novels. The audioplay series (‘Hörspiele’), which has been in production since 1979, has become particularly popular.
Die drei ??? The German series adopted innovations from the Crimebusters series; for example, the Three Investigators have driving licences and own cars. It introduced new elements, including the lock pick, which Peter uses regularly. The German books often contain references to the American original series and bring back characters from it.
Published books The bold numbers in square brackets are the chronological order these take place in the German continuity which includes the original series and Crimebusters. Bold titles mean the episode was also translated into English to serve as a school book.
Tatort Zirkus (Crime Scene: Circus) (1993, by B. J. Henkel-Waidhofer) ... und der verrückte Maler (The Insane Painter) (1993, by B. J. Henkel-Waidhofer) Giftiges Wasser (Toxic Water) (1993, by B. J. Henkel-Waidhofer) Dopingmixer (Runaway Success) (1994, by B. J. Henkel-Waidhofer) ... und die Rache des Tigers (The Revenge of the Tiger) (1994, by B. J. Henkel-Waidhofer) Spuk im Hotel (Haunted Hotel) (1994, by B. J. Henkel-Waidhofer) Fußball-Gangster (Soccer Gangsters) (1995, by B. J. Henkel-Waidhofer) Geisterstadt (Ghost Town) (1995, by B. J. Henkel-Waidhofer) Diamantenschmuggel (Diamond Smuggling) (1995, by B. J. Henkel-Waidhofer) ... und die Schattenmänner (The Shadowmen) (1995, by B. J. Henkel-Waidhofer) Geheimnis der Särge (The Mystery of the Coffins) (1996, by B. J. Henkel-Waidhofer) Schatz im Bergsee (The Treasure of the Mountain Lake) (1996, by B. J. Henkel-Waidhofer) Späte Rache (Late Revenge) (1996, by B. J. Henkel-Waidhofer) Schüsse aus dem Dunkel (Shots from the Dark) (1996, by B. J. Henkel-Waidhofer) Die verschwundene Seglerin (The Missing Sailor) (1996, by B. J. Henkel-Waidhofer) Dreckiger Deal (Dirty Deal) (1996, by B. J. Henkel-Waidhofer) Die Spur des Raben (The Trail of the Raven) (1997, by André Marx) Poltergeist (Poltergeist) (1997, by André Marx) ... und das brennende Schwert (The Burning Sword) (1997, by André Marx) Pistenteufel (Slope Devil) (1997, by Ben Nevis) Stimmen aus dem Nichts (Voices from the Void) (1997, by André Minninger) Das leere Grab (The Empty Grave) (1997, by André Marx) Verdeckte Fouls (Hidden Fouls) (1998, by Ben Nevis) Im Bann des Voodoo (Voodoo Spell) (1998, by André Minninger) Geheimsache Ufo (Secret Matter: UFO) (1998, by André Marx) Meuterei auf hoher See (Mutiny at Sea) (1998, by André Marx) Musik des Teufels (The Devil's Music) (1998, by André Marx) Die Karten des Bösen (The Hand of Evil) (1998, by André Minninger) Wolfsgesicht (Wolf Face) (1999, by Katharina Fischer) Nacht in Angst (Night of Fear) (1999, by André Marx) Feuerturm (Tower of Fire) (1999, by Ben Nevis) Tödliche Spur (Deadly Trail) (1999, by André Marx) Vampir im Internet (Vampire on the Internet) (1999, by André Minninger) ... und das Geisterschiff (The Ghost Ship/The Haunted Ship) (2000, by André Marx) Todesflug (Flight of Death) (2000, by Ben Nevis) Labyrinth der Götter (Labyrinth of the Gods) (2000, by André Marx) ... und der rote Rächer (The Red Avenger) (2000, by Katharina Fischer) Das schwarze Monster (The Black Monster) (2000, by André Marx) Botschaft von Geisterhand (Message from a Ghost) (2000, by André Marx) Insektenstachel (Stinger) (2001, by André Minninger) Rufmord (Slander) (2001, by André Minninger) Tal des Schreckens (Valley of Terror/Valley of Horror) (2001, by Ben Nevis) Doppelte Täuschung (Double Deception) (2001, by André Marx) ... und das Hexenhandy (The Curse of the Cell Phone) (2001, by André Minninger) Toteninsel (Island of Death) (2001, by André Marx) Das Erbe des Meisterdiebs (The Legacy of the Master-Thief/Mysterious Testament) (2002, by André Marx) Gift per E-Mail (Poison By E-mail/Poisoned E-Mail) (2002, by Ben Nevis) ... und der Nebelberg (The Mountain of Mist) (2002, by André Marx) Der Mann ohne Kopf (The Man without a Head) (2002, by André Minninger) ... und der Schatz der Mönche (The Treasure of the Monks) (2002, by Ben Nevis) Die sieben Tore (The Seven Gates) (2002, by André Marx) Gefährliches Quiz (Dangerous Quiz/Dangerous Quiz Show (2003, by Marco Sonnleitner) Panik im Park (Panic in the Park) (2003, by Marco Sonnleitner) Die Höhle des Grauens (The Cave of Horror) (2003, by Ben Nevis) Das Auge des Drachen (The Eye of the Dragon) (2003, by André Marx) Schlucht der Dämonen (The Canyon of Demons) (2003, by Marco Sonnleitner) Die Villa der Toten (The Mansion of the Dead) (2003, by André Marx) Der Feuerteufel (Firebug) (1999, by André Marx as paperback Halloween special; released as hardback in 2004) Der finstere Rivale (The Sinister Rival) (2004, by André Marx) Codename: Cobra (Codename: Cobra) (2004, by Marco Sonnleitner) Auf tödlichem Kurs (On A Deadly Course) (2004, by Ben Nevis) Der schwarze Skorpion (The Black Scorpion) (2004, by Marco Sonnleitner) Das düstere Vermächtnis (The Grim Legacy) (2004, by Ben Nevis) Der geheime Schlüssel (The Secret Key) (2004, by André Marx) Spur ins Nichts (Nowhere to Go/Evil Games) (2005, by André Marx) ... und der Geisterzug (The Ghost Train/The Mystery of the Ghost Train) (2005, by Astrid Vollenbruch) Fußballfieber (Soccer Mania) (2005, by Marco Sonnleitner) Schrecken aus dem Moor (Terror from the Swamp) (2005, by Marco Sonnleitner) Geister-Canyon (Ghost Canyon) (2005, by Ben Nevis) Feuermond (Moon of Fire) (2005, by André Marx) SMS aus dem Grab (Text Message from the Grave/The Pharaoh’s Message) (2006, by Ben Nevis) Schwarze Madonna (Black Madonna) (2006, by Astrid Vollenbruch) Schatten über Hollywood (Shadow Over Hollywood/Hollywood Horrors) (2006, by Astrid Vollenbruch) Spuk im Netz (Web Phantom) (2006, by Astrid Vollenbruch) Der Fluch des Drachen (The Curse of the Dragon) (2006, by André Marx) Haus des Schreckens (House of Terror) (2006, by Marco Sonnleitner) Fluch des Piraten (The Pirate’s Curse) (2007, by Ben Nevis) Fels der Dämonen (Rock of the Demons) (2007, by Marco Sonnleitner) Der tote Mönch (The Dead Monk) (2007, by Marco Sonnleitner) Die geheime Treppe (The Hidden Stair) (2007, by Marco Sonnleitner) ... und das versunkene Dorf (The Sunken Village/Ghost Village) (2007, by André Marx) Pfad der Angst (Path of Fear) (2007, by Astrid Vollenbruch) ... und die Fußball-Falle (Soccer Case/Soccer Trap) (2008, by Marco Sonnleitner) Das Geheimnis der Diva (The Secret of the Diva) (2008, by Astrid Vollenbruch) Stadt der Vampire (Vampire City) (2008, by Marco Sonnleitner) Zwillinge der Finsternis (Twins of Doom) (2008, by Marco Sonnleitner) Tödliches Eis (Deadly Ice/Arctic Adventure) (2008, by Kari Erlhoff) ... und die Poker-Hölle (The Gambling Joint) (2008, by Marco Sonnleitner) Grusel auf Campbell Castle (Horror at Castle Campbell) (2009, by Marco Sonnleitner) ... und die Rache der Samurai (The Revenge of the Samurai) (2009, by Ben Nevis) Der Biss der Bestie (The Bite of the Beast) (2009, by Kari Erlhoff) Schwarze Sonne (Black Sun) (2009, by Marco Sonnleitner) ... und die feurige Flut (The Fiery Flood) (2009, by Kari Erlhoff) Der namenlose Gegner (The Nameless Foe) (2009, by Kari Erlhoff) Geisterbucht (Ghost Bay) (2010, by Astrid Vollenbruch) ... und das Fußballphantom (The Soccer Phantom) (2010, by Marco Sonnleitner) Skateboardfieber (Skateboard Fever) (2010, by Ben Nevis) Botschaft aus der Unterwelt (Message from the Underworld) (2010, by Kari Erlhoff) ... und der Meister des Todes (The Master of Death) (2010, by Kari Erlhoff) Im Netz des Drachen (In the Net of the Dragon) (2010, by Marco Sonnleitner) Im Zeichen der Schlangen (In the Sign of the Snakes) (2011, by Hendrik Buchna) Nacht der Tiger (Night of the Tigers) (2011, by Marco Sonnleitner) ... und der Feuergeist (The Fire Ghost) (2011, by Marco Sonnleitner) ... und der schreiende Nebel (The Screaming Fog) (2011, by Hendrik Buchna) Geheimnisvolle Botschaften (Mysterious Messages) (2011, by Christoph Dittert) Die blutenden Bilder (The Bleeding Pictures) (2011, by Kari Erlhoff) Fußball-Teufel (Soccer Devil) (2012, by Marco Sonnleitner) ... und der verschollene Pilot (The Missing Pilot) (2012, by Ben Nevis) Im Schatten des Giganten (In the Shadow of the Giant) (2012, by Kari Erlhoff) GPS-Gangster (GPS Gangster) (2012, by Marco Sonnleitner) ... und das blaue Biest (The Blue Beast) (2012, by Hendrik Buchna) ... und die brennende Stadt (The Burning City) (2012, by Christoph Dittert) ... und das Phantom aus dem Meer (The Phantom from the Sea) (2013, by Marco Sonnleitner) Straße des Grauens (Street of Horror) (2013, by Kari Erlhoff) Die Spur des Spielers (The Player’s Trace) (2013, by André Marx) ... und das Tuch der Toten (The Cloth of the Dead) (2013, by Marco Sonnleitner) ... und der Eisenmann (The Ironman) (2013, by Ben Nevis) Dämon der Rache (Demon of Revenge) (2013, by Hendrik Buchna) ... und der gestohlene Sieg (The Stolen Victory) (2014, by Marco Sonnleitner) Schattenwelt (Shadow World) (2014, by Christoph Dittert, Kari Erlhoff and Hendrik Buchna - each contributing one part of the story) Der Geist des Goldgräbers (The Ghost of the Gold Digger) (2014, by André Marx) Der gefiederte Schrecken (The Feathered Horror) (2014, by Christoph Dittert) Die Rache des Untoten (The Revenge of the Undead) (2014, by Marco Sonnleitner) ... und die flüsternden Puppen (The Whispering Dolls) (2015, by André Minninger) Im Haus des Henkers (In the Hangman’s House) (2015, by Marco Sonnleitner) Das Kabinett des Zauberers (The Magician’s Cabinet) (2015, by André Marx) ... und der letzte Song (The Last Song) (2015, by Ben Nevis) ... und der Hexengarten (The Witch’s Garden) (2015, by Kari Erlhoff) ... und das silberne Amulett (The Silver Amulet) (2016, by Marco Sonleitner) Insel des Vergessens (Island of Oblivion) (2016, by André Marx) ... und der Mann ohne Augen (The Man Without Eyes) (2016, by Christoph Dittert) Signale aus dem Jenseits (Signals from the Beyond) (2016, by André Minninger) ... und der unsichtbare Passagier (The Invisible Passenger) (2016, by Hendrik Buchna) ... und die Kammer der Rätsel (The Chamber of Riddles) (2016, by Ben Nevis) Verbrechen im Nichts (Crime in the Void) (2017, by Kari Erlhoff) Im Bann des Drachen (Under the Spell of the Dragon) (2017, by Christoph Dittert) Schrecken aus der Tiefe (Fright from the Depths) (2017, by Marco Sonnleitner) ... und die Zeitreisende (The Time Traveler) (2017, by André Minninger) Im Reich der Ungeheuer (In the Realm of Monsters) (2017, by Hendrik Buchna) Geheimnis des Bauchredners (Secret of the Ventriloquist) (2017, by André Marx) ... und der grüne Kobold (The Green Goblin) (2018, by Marco Sonnleitner) Im Auge des Sturms (In the Eye of the Storm) (2018, by Kari Erlhoff) Die Legende der Gaukler (The Legend of the Jugglers) (2018, by Christoph Dittert) Höhenangst (Vertigo) (2018, by André Minninger) Feuriges Auge (Fiery Eye) (2018, by André Marx) Das weiße Grab (The White Grave) (2018, by Ben Nevis)