Sir Arthur Conan Doyle did his bit for football in Portsmouth, helping to found Portsmouth AFC in the late 19th century. So crumblingly unreconstructed is Fratton Park that Doyle would have still felt at home on Saturday.
He would even have found a robbery for Sherlock Holmes to investigate - provided he took Aidy Boothroyd as a plausible witness. The Watford manager was sure that a crime had been committed. "It was a bad decision, a wrong decision," he said of the late penalty given against his team. "We might have had two penalties and theirs was offside." He suggested an appropriate punishment for the fiend in black: "I'm not advocating prison, the stocks will do."
English football is currently so overflowing with unlikely exotica that it is even manifest at Watford: their forward Hameur Bouazza had been named in the Algerian squad for a midweek friendly against Burkina Faso that was played in Provence.
But there was little of such cosmopolitan allure at Fratton Park. This was a match from old England, the result emerging from a whirl of raw endeavour, intermittent skill and questionable penalty decisions.
Boothroyd had a point about Portsmouth being offside before Jay Demerit grabbed at Kanu for the penalty. Also, earlier, the ball had made contact with Linvoy Primus's hand as he had cleared from the Pompey box.
But, then again, Watford's goal emerged from inattentiveness by the match officials. They were given a corner when the ball went out off their own striker, Ashley Young. The corner was taken by Young and missed by David James. DeMerit was left with a free header for the opening goal.
Watford are so direct that Harry Redknapp inadvertently referred to them as "Wimbledon" after the game. But he was also quick to cite their strengths.
"That was the toughest game we've had here," the Pompey manager said. "We've beaten Blackburn here and Wigan, but today was tougher than any side we've played here. They work hard and they know what they're doing - I wouldn't bet on Watford going down."
Redknapp also impishly dismissed stories about Ajax pursuing Kanu. "What, the kitchen cleaner? I hear AC Milan are after me. Maybe I'll go and see the chairman and see if he'll give me a new deal." It was Kanu who won the match for Portsmouth. On 44 minutes, amid a goalmouth scramble, he contorted his crane-fly physique to chip over Ben Foster. Then he won the penalty that Lomana LuaLua confidently converted.
This 89th-minute winner put Portsmouth in third place and left Watford in the relegation zone. Next for Watford come home matches against Blackburn and Sheffield United. These look like matches they need a win from and Boothroyd remains confident. When asked if his team would stay up, he was without hesitation. "Absolutely - there are three worse teams than us."
Which teams these are he would not say. Given Watford's lack of both luck and guile against Portsmouth, their detection might just be a job worthy of Mr Holmes.
Goals: DeMerit (32) 0-1; Kanu (44) 1-1; LuaLua pen (89) 2-1.
Portsmouth (4-4-2) James; Pamarot, Primus, Campbell, Stefanovic; Thompson (Cole, 63), Davis, Mendes, Kranjcar; LuaLua, Kanu. Substitutes not used: Kiely (gk), O'Brien, Fernandes, Koroman.
Watford (4-4-2) Foster (Lee, h-t); Doyley, Mackay, DeMerit, Stewart; Smith, Spring, Mahon, Bouazza (Priskin, 34); Henderson (Chambers, 77), Young. Substitutes not used: Shittu, Bangura.
Referee: C Foy (Merseyside).
Booked: Portsmouth Thompson; Watford DeMerit, Stewart, Priskin.
Man of the match: Kanu.