Bisky was a Redwall Abbey mouse, and a descendant of Gonff the Mousethief, several times removed. By this bloodline, he was very distantly related to many creatures; namely, Samolus Fixa, Dandin, Columbine, Gonff II, Abbess Bryony, and the Gonfelin Thieves. He was also the husband of Spingo, the father of Andio, the brother-in-law of Gobbo, Bumbo, and Tingo, and the son-in-law of Nokko and Filgo.
Bisky and his friend Dwink had a tendency to get into trouble with their elders for causing trouble - pillow fights, cheeking older beasts, and the like. Encouraged by tales told by Samolus, and the discovery of writings belonging to Gonff, Columbine, and Young Dinny, the pair joined in with the quest to find the four missing Doomwyte Eyes, jewels of fabulous worth. During the course of their search, they convinced Umfry Spikkle to desert his post as door guard; this action earned all three of them a session cleaning the cellars, as punishment.
While in the cellar, Bisky discovered a door leading to an underground cave system. Along with Dwink, Samolus, Umfry, Gullub Gurrpaw, Skipper Rorgus, and Bosie, he entered the tunnel to search it for the Doomwyte eyes. The search party encountered Chigid and the Painted Ones, who captured Bisky and took him back above ground to their lair. There he was tormented by Chigid's son Jeg, until the Painted Ones also captured the young shrew Dubble. With the ingenious Dubble's help, Bisky managed an escape; however, the two were soon recaptured, this time by the Gonfelins.
Once the Gonfelins realized Bisky and Dubble were not a threat to them, they allowed the pair to become allies with them. Together, they led an attack on the Painted Ones, meeting up with a group of Guosim and Redwallers who had the same idea; the vermin were soon routed. It was during this time that Bisky met Spingo, with whom he instantly became smitten.
When Dubble went missing during the attack, Bisky and Spingo tracked him to the hillside where Zaran the Black was attempting to cause a landslide, to kill Korvus Skurr and his villainous allies. The three young beasts helped the otter with her excavation, until a large rock collapsed part of the hill and trapped Spingo underground. Bisky and Dubble went back to Redwall to bring back help; when the rescue party arrived, their attempts to dig out Spingo collapsed the hill even further, causing the moles and the mousemaid to fall into the cavern where Skurr and his minions lived. Bisky ran in and rescued Spingo, suffering from Bloodwrath as he fought his way out of the tunnel to freedom. Many seasons later, he wed her, and they had their daughter, Andio.