Only Fools and Horses Wiki
Thicker than Water
Series 03, Episode 08
Thicker than Water.jpg
Air Date December 25, 1983
Written by John Sullivan
Director Ray Butt
Length 30 minutes
Previous episode "Who's a Pretty Boy?"
Next episode "Licensed to Drill"
List of episode

Del and Rodney's long-absent father Reg returns to Peckham and soon outstays his welcome.


While Del Boy is off on another date, Rodney and Grandad are watching the movie Sleepless Nights on Christmas Day, when a stranger appears at the door. The stranger turns out to be Del and Rodney's father (and Grandad's son) Reg, who had abandoned them 18 years earlier after the death of their mother Joan. When Del learns of Reg's return, he intends to throw him out, but Rodney and Grandad persuade Del to give him a chance. Reg tells his two sons and father that he has been living in Newcastle, and has recently been diagnosed with a hereditary blood disorder.

Thicker than water.jpg

Del and Rodney quickly take blood tests, which both turn out negative, but Grandad notices on their results that they have different blood types. Grandad explains that around the time that Rodney was born, Reg and Joan were having frequent arguments, and Joan flirted with other men. Del and Grandad thus both assume that Rodney has a different father and tell him the news, with Del concluding that Rodney is a "whodunnit". However, when Reg returns having checked his own and Grandad's blood groups, he reveals that it is in fact Del who has the alien blood group.

After spending the night at Trigger's place, Del drowns his sorrows at The Nag's Head, while Reg moves in permanently, wearing Del's clothes, spending time with Rodney, and taunting Del for being a "lone ranger", at one point shouting "Hi-ho silver!" at him. Rodney reassures Del that children with the same parents can have different blood groups and recommends that he visit Dr. Becker, the Trotter family's doctor, again to clarify the results. Del at first refuses, as Becker was with their mother before her death, and so did not want him to realise that she was seeing different men.

The next evening, Reg is clearly outstaying his welcome at the flat, having spent all of Rodney and Grandad's money, drunk all their beer, and even written a bet on one of Rodney's GCE certificates. Del returns home and reveals that he took Rodney's advice and went to see Dr. Becker again, who confirmed that his blood type was actually "A" and not "AB", as recorded on the results, and that someone - Reg - had altered them in an attempt to isolate Del and take his place in Nelson Mandela House. Furthermore, Dr. Becker made some background checks, which found that Reg was actually a porter at the Newcastle infirmary, not a patient, and was on the run after stealing numerous items from the hospital, including a doctor's scooter. All but defeated, Reg decides to leave, and the Trotters are glad to see him go, although Del still gives him some money on his way out.

Featured characters

Other notes

Story arc

  • This episode hints that Del and Rodney do not share the same father. The mystery continues in "The Frog's Legacy", only this time the suggestion is that it is actually Rodney who was the product of an affair between their mother Joan and gentleman thief Freddie "The Frog" Robdal. This is confirmed in the final episode of the series, "Sleepless in Peckham", and is the central plot of the first episode of the prequel series Rock & Chips in which Freddie (played by Nicholas Lyndhurst) has the affair with Joan before Rodney was born.

Production goofs

  • The Dining table and chairs are not present in the lounge until Del enters the flat.

DVD cuts and edits

  • Del and Rodney's dialogue about Reg not being sure if Grandad was dead or alive had been cut, possibly due to sentimental reasons, as Lennard Pearce died in 1984 during the filming of the fourth season.