Titus Welliver and Mark Wahlberg faced their fear of heights together on Transformers: Age of Extinction

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Some people fear snakes or clowns. For Titus Welliver and Mark Wahlberg, however, it's heights that frighten them.

The two discovered their mutual fear while shooting Transformers: Age of Extinction together. Speaking recently with PeopleTV's Lola Ogunnaike, Welliver opened up about his experience shooting the 2014 blockbuster.

"I’ve never run or had such a physically demanding role," the Bosch actor said. "Mark and I tried to do as much of that stuff as we could that was safe, but we both hate heights."

Welliver said that he and Wahlberg bonded over their nerves during an action sequence in the film that takes place on a rooftop. "At one point between takes we were both leaning against the wall just facing the wall because neither one of us wanted to turn around and look behind us to see the drop," he recalled. "Mark turned to me at one point when we were there and he went, 'Yeah a couple of real tough guys.' And I went, 'You know, when it comes to this, I’m not even going to try and front like I don't have an issue with it.'"

The film, which was directed by Michael Bay, also starred Nicola Peltz, Jack Reynor, Stanley Tucci, and Kelsey Grammar. It was the fourth film in the popular Transformers series.

For more with Welliver, check out the video above, and watch his full episode of Couch Surfing here.

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