Will Ferrell and John C. Reilly have unparalleled on-screen chemistry.

The “Holmes and Watson” stars appeared on “Jimmy Kimmel Live!” Wednesday night and talked about reuniting for the film after starring together in “Talladega Nights” and “Step Brothers” back in the 2000s.

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In fact, their affection for each other is so great they couldn’t express themselves with words alone. They had to do it in song.

Midway through the interview, music started behind them and the pair launched into the Peaches & Herb classic “Reunited”.

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Earlier in the interview, Ferrell and Reilly talked about filming their new movie in England.

“I thought I was having a psychotic break,” Reilly revealed. “I got home and I stopped drinking four pots of tea a day and I was fine! Turns out it was all that English tea.”