TORONTO (CP) - It's only fitting that David Schwimmer, who played the lovable Ross Geller for 10 years on the sitcom 'Friends,' was also surrounded by friends on the set of his first feature film as a director.

The Emmy-nominated actor says English actor-writer Simon Pegg, who plays the lead in Schwimmer's new film 'Run, Fatboy, Run,' is a good pal he met six years ago on the set of the TV mini-series 'Band of Brothers.'

Co-star Thandie Newton was also a good friend of a friend, says Schwimmer, while several other cast members in the U.K.-based romantic comedy had chummed around for years prior to jumping onboard his project.

The result was constant laughter and pranks that helped lighten the mood on what turned into a tough 35-day low-budget shoot in over 50 locations in London, England, last November and December.

"Thandie was the one that was the big prankster," the 40-year-old said with a laugh Monday in an interview at the Toronto International Film Festival where 'Run, Fatboy, Run' is screening.

"She was pulling all kinds of pranks on Simon, constantly. If you walked in Simon's trailer at any given time, you'd find, like, a fake poo in his toilet that she had made out of a Baby Ruth (chocolate bar), or you would find, like, a pair of white underwear that she had covered with dark brown Marmite so anyone who walked in his trailer during the day would see his underwear on the floor and think he'd crapped himself."

Then there was the recent press junket in the U.K., where the film is already in theatres (it opens in North American on Oct. 26).

"At 10 a.m. in the morning, we're all kind of exhausted from the night before - it was the premiere and we were all a little hung over and everything - so we start out with a junket and we were in our individual rooms and all of us had like four bottles of water by our chairs," said Schwimmer, who has homes in Los Angeles and New York.

"Simon goes for his first swig of water - Thandie had filled all, ALL, of his giant water bottles with vodka, so he goes for his first big swig and just (spits up) all over the reporter, everywhere. It was great."

'Run, Fatboy, Run' stars Pegg as Dennis, a hapless, chain-smoking loser who somehow winds up with an attractive fiancee named Libby (Newton), but dumps her just hours before their wedding and weeks before she's due to give birth to their child.

He regrets his decision, though, and with the help of his alcoholic buddy (Dylan Moran) tries to win her back by declaring that he's going to run the same marathon that her new fit and wealthy boyfriend, Whit (Hank Azaria), is going to run.

Schwimmer said he'd been looking to do a feature film for nearly a year, either a comedy or a drama, and he loved the tone of the script written by Chicago-born writer-actor-director Michael Ian Black.

"I was kind of surprised to find myself laughing as hard as I was, out loud, during the read," said Schwimmer, whose prior directing experience included about a dozen episodes of "Friends," as well as countless theatre productions and a few TV pilots.

"And then by the end of it to be as moved as I was - maybe it was just an emotional day, I don't know, but I was really moved by his story."

The original script involved a marathon in New York City, but once it was optioned by a London-based company, it was rewritten - with Pegg's help - and relocated across the pond.

Schwimmer said he isn't concerned that his first feature film as a director takes place outside his home country.

"I didn't think, 'Yes, this is the stamp of the Schwimmer dynasty of filmmaking,' " he said.

"My goal was to kind of just put on screen what I read. ... All my favourite movies are driven by performances and my goal was just to create an atmosphere in which these great actors could just be their best."