LONDON (AP) — Versatile British actor Paul Ritter, who appeared in the “Harry Potter” franchise and played a key figure behind nuclear disaster in “Chernobyl,” has died at 54. Ritter agent said the actor died at home on Monday evening and had been suffering from a brain tumor. Ritter was a familiar face to British television viewers, famous as eccentric patriarch Martin Goodman in the Channel 4 sitcom “Friday Night Dinner.” He also played ill-fated nuclear engineer Anatoly Dyatlov in the HBO drama “Chernobyl” and the wizard Eldred Worple in “Harry Potter and The Half-Blood Prince.” Ritter also appeared as a devious political operative in the James Bond film “Quantum of Solace” and had frequent stage roles.