From the Super Mario Wiki
“Elementary, my dear Kooparity. You're a cross between a lizard and an inferior species of toad. Your brain is smaller than a peanut. You got the lowest grades in your school and hold the world record for flunking kindergarten the most times. When you were little, the other Koopas nicknamed you "Lizard Lips" and never let you play with them. You were a naughty lily-livered bully boy and wet the bed until you were twelve. ”
In The Super Mario Bros. Super Show! episode "The Adventures of Sherlock Mario", Mario, Luigi, Toad and Princess Toadstool ventured to Herlock Solmes' home city of Victoria in search of Herlock Solmes, who had agreed to meet them at midnight to discuss plans on helping them defeat King Koopa.
Before Mario, Luigi, Toad and Princess Toadstool ever had the chance to meet him though, Herlock Solmes was kidnapped by Professor Kooparity, whose plans to destroy Victoria Herlock Solmes had discovered. Losing his hat and magnifying glass in a scuffle with Professor Kooparity, Herlock Solmes was taken to Professor Kooparity's sewer headquarters, where he was tied to a chair and mocked by Professor Kooparity, Mouser, Tryclyde and a Koopa Troopa. As Professor Kooparity taunted Herlock Solmes, he jokingly said that he bet Herlock Solmes couldn't figure out what Professor Kooparity was planning to do; Professor Kooparity was left dumbstruck though, when Herlock Solmes correctly deduced that Professor Kooparity, Mouser, Tryclyde and the Koopa Troopa were going to steal the Retro Router from the Tower of Victoria and use it to flood all of Victoria.
Later, after Professor Kooparity, Mouser, Tryclyde and the Koopa Troopa stole the Retro Router and were preparing to use it to flood Victoria, Professor Kooparity gloated that once he flooded Victoria, he would be one of the vilest villains ever and asked Herlock Solmes, who was still tied to a chair, what he thought of him now; after being asked this by Professor Kooparity, Herlock Holmes proceeded to reveal several embarrassing secrets of Professor Kooparity and mocked him, which enraged Professor Kooparity and caused the nearby Mouser, Tryclyde and Koopa Troopa laugh hysterically.
Eventually, Herlock Solmes was released from his confinement by Professor Kooparity by Mario, Luigi, Toad and Princess Toadstool, who managed to find Professor Kooparity's sewer headquarters and defeated Professor Kooparity and the Koopa Pack and destroyed the Retro Router, stopping it from flooding all of Victoria.
Afterward, at Herlock Solmes house on Bonkers Street, Herlock Solmes gratefully thanked Luigi, Toad and Princess Toadstool for stopping Professor Kooparity from flooding Victoria, as Mario searched Herlock Solmes house for some food. Before Herlock Solmes could stop him, Mario opened the carrying cage of the Killer Kitty of the Caskervilles thinking it to be a lunchbox. Once freed by Mario, the Killer Kitty of the Caskervilles proceeded to clamp down on Mario's hand, leaving Herlock Solmes, Luigi, Toad and Princess Toadstool to try and pull the Killer Kitty of the Caskervilles off Mario's hand.