 Once inside , the rebels began to hunt down their key targets , and found Archbishop Sudbury and Robert Hales in the chapel of the White Tower . Along with William Appleton , John of Gaunt 's physician , and John Legge , a royal sergeant , they were taken out to Tower Hill and beheaded . Their heads were paraded around the city , before being affixed to London Bridge . The rebels found John of Gaunt 's son , the future Henry IV , and were about to execute him as well , when John Ferrour , one of the royal guards , successfully interceded on his behalf . The rebels also discovered Lady Joan and Joan Holland , Richard 's sister , in the castle but let them go unharmed after making fun of them . The castle was thoroughly looted of armour and royal paraphernalia . 
